The number of workers that will lose job is 1.

Before the minimum wage, the number of workers employment is determined at the intersection of ??????labor supply and labor demand curves. It happens at wage $6. At wage $6, number of labor supplied is equal to the number of labor demanded at 5 workers. The market wage is $6.

Now, a minimum wage of $7 is imposed. It is above the market wage. So, it is a binding minimum wage.

At $7, the number of labor supplied is 6 workers and number of labor demanded is 4 workers. It means that 6 workers are willing to work at the given wage but only 4 workers are demanded at $7 wage. So, only 4 workers will be hired in the market after minimum wage has been imposed.

5 workers were employed before the minimum wage and 4 workers are employed after the imposition of minimum wage at $7.

5-4 = 1

So, 1 worker loses his/her job because of the minimum wage.