A firm's year-end retained earnings balances are $670,000 and $560,000, for 2014 and 2015 respectively. The firm paid $10,000 in dividends in 2015.

The firm's net profit after taxes in 2015 = (Firm's year-end retained earnings balance in 2015 - firm's year-end retained earnings balance 2014 + dividend payment)

= ($560,000 -$670,000 + $10,000)

= - $100,000

Therefore correct answer is option d. - $100,000

Gross profit is of the company = sales revenue - cost of goods sold

The gross profit of the company equals Sales or revenue minus cost of goods sold (COGS) which is direct cost associated with producing goods or services of the company.

Therefore correct answer is option b. sales revenue minus cost of goods sold