Someone plz explain why i got these wrong! i don't understand it. ignore my writing

Imogene invested $8,000 in a bank account that pays 8 percent simple interest at the end of each year. her friend invested the same amount in stocks where the growth of the investment is represented as 2,000 times the square root of 2 less than the time lapsed in years. if y1 and y2 represent the amount earned in dollars and t is the time lapsed in years, which system of equations correctly represents the situation?

The cost of using a service is $0.25 per min. what equation correctly represents the total cost c, in dollars, for d days of use?

The difference between two numbers is one. three times the larger number minus two times the smaller number is 9. what are the two numbers