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1 What is the output of the following code : L = ['a','b','c','d'] print ""

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1

What is the output of the following code : L = ['a','b','c','d'] print "".join(L)

SELECT THE CORRECT ANSWER

Error

None

abcd

['a','b','c','d']

 

2

To start Python from the command prompt, use the command ________.

SELECT THE CORRECT ANSWER

execute python

python3

run python

Go python

 

3

Which of the following code is correct?

SELECT THE CORRECT ANSWER

print(""Programming is fun"")print(""Python is fun"");

print(""Programming is fun"")print(""Python is fun"")

print(""Programming is fun)print(""Python is fun"")

print"(""Programming is fun)print(""Python is fun"")"

 

4

In Python, a syntax error is detected by the ________ at _________.

SELECT THE CORRECT ANSWER

compiler/at compile time

interpreter/at runtime

compiler/at runtime

interpreter/at compile time

 

5

Which of the following statement prints smith\exam1\test.txt?

SELECT THE CORRECT ANSWER

print("smith\exam1\test.txt")

print("smith\"exam1\""test.txt"")"

print("smith"\exam1"\test.txt")

print("smith\\exam1\\test.txt")

 

6

If a function does not return a value, by default, it returns ___________.

SELECT THE CORRECT ANSWER

None

Int

Double

null

 

7

Consider the following incomplete code: def f(number): # Missing function body print(f(5)) The missing function body should be ________.

SELECT THE CORRECT ANSWER

return "number"

print(number)

print("number")

return number

 

8

What will be displayed by the following code?

x = 1

def f1():

  y = x + 2

  print(y)

f1()

print(x)

SELECT THE CORRECT ANSWER

1 3

The program has a runtime error because x is not defined.

1 1

3 1

 

9

Which of the following function headers is correct?

SELECT THE CORRECT ANSWER

def f(a = 1, b):

def f(a = 1, b, c = 2):

def f(a = 1, b = 1, c = 2):

def f(a = 1, b = 1, c = 2, d):

 

10

Suppose list1 is [3, 4, 5, 20, 5, 25, 1, 3], what is list1 after list1.pop(1)?

SELECT THE CORRECT ANSWER

[3, 4, 5, 20, 5, 25, 1, 3]

[1, 3, 3, 4, 5, 5, 20, 25]

[3, 5, 20, 5, 25, 1, 3]

[1, 3, 4, 5, 20, 5, 25]

 

11

What is the output of the following program: y = 8 z = lambda x : x * y print (z(6))

SELECT THE CORRECT ANSWER

48

14

64

y is not defined

 

12

What is the output of the following code? a=""hello"" =list((x.upper(),len(x)) for x in a) print(b)

SELECT THE CORRECT ANSWER

[('H', 1), ('E', 1), ('L', 1), ('L', 1), ('O', 1)].

[('HELLO', 5)]

[('H', 5), ('E', 5), ('L', 5), ('L', 5), ('O', 5)].

Syntax error

 

13

What is the output of the function shown below? hex(15)

SELECT THE CORRECT ANSWER

F

0xf

0Xf

0xF

 

14

Which piece of code creates an empty class?

SELECT THE CORRECT ANSWER

class A: return

class A: pass

class A:

You cannot create empty class in python

 

15

What are the methods which begin and end with two underscore characters called?

SELECT THE CORRECT ANSWER

Special Methods

In-Built methods

User-defined methods

Additional methods

 

16

What does print(Test.__name__) display (assuming Test is the name of the class) ?

SELECT THE CORRECT ANSWER

()

Exception is thrown

Test

__main__

 

17

Which type of inheritance is illustrated by the following code? class student{ public: int marks; }; class topper: public student { public: char grade; }; class average{ public: int marks_required; }; class section: public average{ public: char Student_name[10]; }; class overall: public average{ public: int students; };

SELECT THE CORRECT ANSWER

Multiple Inheritance

Hierarchical Inheritance

Multilevel Inheritance

Single Inheritance

 

18

What is the output of the following piece of code when executed in the Python shell? class A: pass class B(A): pass obj=B() isinstance(obj,A)

SELECT THE CORRECT ANSWER

TRUE

Syntax error

FALSE

Invalid method for classes.

 

19

What is the output of the below program? x = 50 def func(): global x print('x is', x) x = 2 print('Changed global x to', x) func() print('Value of x is', x)

SELECT THE CORRECT ANSWER

x is 50 Changed global x to 2 Value of x is 50

x is 50 Changed global x to 2 Value of x is 2

x is 50 Changed global x to 50 Value of x is 50

None of the mentione

 

20

Which of the following is a features of DocString?

SELECT THE CORRECT ANSWER

Provide a convenient way of associating documentation with Python modules, functions, classes, and methods

All functions should have a docstring

Docstrings can be accessed by the __doc__ attribute on objects

All of the mentioned

 

21

Mathematical operations can be performed on a string. State whether true or false.

SELECT THE CORRECT ANSWER

TRUE

FALSE

 

22

Following set of commands are executed in shell, what will be the output? >>>str=""hello"" >>>str[:2] >>>

SELECT THE CORRECT ANSWER

he

lo

olleh

hello

 

23

Carefully observe the given code and give the answer. def example(a): a = a + '2' a = a*2 return a >>>example(""hello"")

SELECT THE CORRECT ANSWER

Indentation error

Cannot perform mathematical operations on strings

hello2

hello2hello2

 

24

What is the output of the following : d = {0: 'a', 1: 'b', 2: 'c'} for x in d.values(): print(d[x])

SELECT THE CORRECT ANSWER

0 1 2

a b c

0 a 1 b 2 c

Causes a key error

 

25

What is the output of the following code: for i in ''.join(reversed(list('abcd'))): print (i)

SELECT THE CORRECT ANSWER

a b c d

d c b a

error

none of the mentioned

 

26

Which of the following is a sequence data type in Python?

SELECT THE CORRECT ANSWER

Long

Float

String

Integer

 

27

Which of the following is a valid list in Python?

SELECT THE CORRECT ANSWER

[ 1,2,3.4]

[1,”a”,6]

[1,[2,3],”s”]

All of the above

 

28

Which of the following is true for data type conversions?

SELECT THE CORRECT ANSWER

Numeric data types can be converted to both tuples and lists

String 1234 can be converted to a numeric data type

Numeric data types can be converted to tuples

Numeric data types can be converted to lists

 

29

Which of the following is required to create a new instance of a class?

SELECT THE CORRECT ANSWER

A constructor

An object

A class

A value returning function

 

30

What are the benefits of functions in Python? Select all that apply.

SELECT THE CORRECT ANSWER(S)

Reducing the duplication of a code

Decomposing complex problems into simpler pieces

Reusing a code

Decreasing modularity

 

31

Which of these shows the correct way of creating an object?

SELECT THE CORRECT ANSWER

Student s = new Student()

s = new Student()

s = Student()

s = Student(s)

 

32

Beautiful Soup library is used for _____.

SELECT THE CORRECT ANSWER

Data wrangling

Web scraping

Plotting

Machine learning

 

33

In hypothesis testing, the proposed model is built on:

SELECT THE CORRECT ANSWER

Entire dataset

Test dataset

Small subset

Training dataset

 

34

Which measure of central tendency is used to catch outliers in the data?

SELECT THE CORRECT ANSWER

Mean

Median

Mode

Variance

 

35

Which of the following is true for statistical analysis? Select all that apply.

SELECT THE CORRECT ANSWER(S)

It is nonscientific

It is based on numbers or statistical values

It is useful in providing complete insight of the data

It is based on generic information

 

36

Which of the following is a limitation of lists?

SELECT THE CORRECT ANSWER

Values cannot be updated in a list

List cannot be iterated

Mathematical operations cannot be applied over the entire list

List cannot hold multiple values of multiple data types

 

37

Which of the following is true for NumPy? Select all that apply.

SELECT THE CORRECT ANSWER(S)

It is the foundational package for mathematical computing in Python

It stores and manipulates data efficiently

It doesn't support multidimensional arrays (ndarray)

It doesn't have tools for reading or writing array-based datasets to disk

 

38

Which of the following methods creates a new array object that looks at the same data?

SELECT THE CORRECT ANSWER

View

Copy

Paste

Deep copy

 

39

Which method is used for label-location indexing by label?

SELECT THE CORRECT ANSWER

iat

iloc

loc

std

 

40

While viewing a dataframe, head() method will _____.

SELECT THE CORRECT ANSWER

Return only the first row

Return only headers or column names of the DataFrame

Return the first five rows of the DataFrame

Throw an exception as it expects parameter(number) in parenthesis

 

41

The result of an operation between unaligned series will have the ________ of the indexes involved.

SELECT THE CORRECT ANSWER

Intersection

Union

Total

None of the above

 

42

Which of the following inputs can be accepted by a DataFrame ?

SELECT THE CORRECT ANSWER

Structured ndarray

Series

DataFrame

All of the above

 

43

Which of the following statements limits both x and y axes to the interval [0, 6]?

SELECT THE CORRECT ANSWER

plt.xlim(0, 6)

plt.ylim(0, 6)

plt.xylim(0, 6)

plt.axis([0, 6, 0, 6])

 

44

Which of the following is used to display plots on the Jupyter notebook?

SELECT THE CORRECT ANSWER

%matplot inline

%matplotlib inline

import matplotlib

import matplotlib.pyplot

 

45

Which parameter should you use to change a plot's transparency?

SELECT THE CORRECT ANSWER

style=

linestyle=

color=

alpha=

 

46

How can you change the default plot size?

SELECT THE CORRECT ANSWER

plt.rcParam['figure.figsize'] = (w, h)

Set 'figure.figsize' in .matplotlibrc file

Both A and B

Can't change the default plot size

 

47

Identify a feature of bell curve. Select all that apply.

SELECT THE CORRECT ANSWER(S)

More dense in the tails

Less dense in the tails

Symmetric around the mean

Less dense in the center

 

48

p-value in hypothesis testing is:

SELECT THE CORRECT ANSWER

Negative when there is Type I error

Only depends on the alternative hypothesis

Only depends on the null hypothesis

The probability of observing extreme values

 

49

In the context of statistical distributions, what does mesokurtic mean?

SELECT THE CORRECT ANSWER

Negative kurtosis

Positive kurtosis

Normal distribution

Partial distribution

 

50

Which of the following machine learning algorithms is used for dimensionality reduction ?

SELECT THE CORRECT ANSWER

PCA

Hierarchical clustering

K-means clustering

Logistic regression

 

51

What is specifying the number of clusters required for?

SELECT THE CORRECT ANSWER

Affinity propagation

K-means clustering

Hierarchical clustering

PCA

 

52

Which of the following is an unsupervised learning technique?

SELECT THE CORRECT ANSWER

Linear regression

Logistic regression

PCA

SVM

 

53

In machine learning, an estimator is a(n):

SELECT THE CORRECT ANSWER

Instance of the model

Predict method

Method for pipeline

Method to fit the data into model

 

54

What is used for dimensionality reduction?

SELECT THE CORRECT ANSWER

Affinity propagation

K-means clustering

PCA

SVM

 

55

In statistics, a Type II error occurs when:

SELECT THE CORRECT ANSWER

A null hypothesis is rejected but should not be rejected

A null hypothesis is not rejected but should be rejected

A test statistic is incorrect

A hypothesis is chosen incorrectly