Solve the blank boxes on the graph and answer the question in red

Question 13 (1 point) jerome is starting a new job. his contract states he will earn $42,000 the first year, and will get a 4% raise per year. which function s(x) represents jerome's salary after a certain number of years, x?

Calculate the average rate of change over the interval [1, 3] for the following function. f(x)=4(5)^x a. -260 b. 260 c. 240 d. -240

Math i have no idea how to do a and b