Gilkey Corporation began the year with retained earnings of $155,000. During the year, the company issued $210,000 of common stock, recorded expenses of $600,000, and paid dividends of $40,000. If Gilkey's ending retained earnings was $165,000, what was the company's revenue for the year?

b. $650,000 is correct but how to get the answer thank you

You have to know the Retained Earnings Formula, which is:
Beginning Retained Earnings + Common Stock issued - Cash Dividends + Net Income (Revenues - Expenses) = Ending Retained Earnings

Rewritten to find Net Income:
Net Income = Ending Retained Earnings - Beginning Retained - Common Stock Issued + Cash dividends + Expenses