I need help on my math question so whats c?

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?

In a class, there are 12 girls. if the ratio of boys to girls is 5: 4 how many boys are there in the class

Plz ( true - false) all triangles have interior angles whose measure sum to 90.