Hey does anyone know the answer please help me

Given the equation f(x)=a(b)x where the initial value is 40 and the growth rate is 20% what is f(4)

Asquare has a side that measures 11 units. what is the area of a circle with a circumference that equals the perimeter of the square? use 3.14 for π, and round your answer to the nearest hundredth. 1519.76 units2 379.94 units2 616.56 units2 154.14 units2

Is it greater than or less than7*3_9*2