What is the relationship between the base of an exponential function and its rate of growth? a. The greater the value of the base, the
greater the function's rate of growth.
b. The base of an exponential function is
unrelated to its rate of growth,
c. The smaller the value of the base, the
greater the function's rate of growth.
d. For each increase in the base, the
function's rate of growth doubles.

1. 2.12 seconds

2. 10 feet

Step-by-step explanation:

1. "Pekka tosses a ball out of a window that is 40 feet in the air.  Its initial velocity is 15 feet per second.  The path of the ball is represented by:

h = -16t² + 15t + 40

How long does it take for the ball to hit the ground (in seconds) rounded to the nearest hundredth?"

When the ball hits the ground, its height is 0:

0 = -16t² + 15t + 40

0 = 16t² − 15t − 40

Solve with quadratic formula:

t = [ -b ± √(b² − 4ac) ] / 2a

t = [ 15 ± √(225 + 2560) ] / 32

t ≈ 2.12 or -1.18

t must be positive, so t = 2.12 seconds.

2. "Tricia bounces a ball in front of her feet.  The path of the ball from the time it hits the ground until it lands on the floor is represented by:

f(x) = -2(x − 3)² + 10

Assuming that Tricia's feet are located at the origin (0, 0), what is the maximum height of the ball (in feet)?"

The function is a parabola.  The vertex of this parabola is at (3, 10).  So the maximum height is 10 feet.