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The formula for the volume of a sphere is , and the formula for the surface area of a sphere is . If a sphere has a surface area of 36π, what is its volume?

(F) 27π

(G) 36π

(H) 54π

(J) 72π

(K) 108π

When a ≠ b, the expression . Which of the following describes the complete set of x values that make this inequality true?

(A) x = -4 only (B) x = 4 only (C) x = - only (D) x < 0 (E) x > 0

Correct Answer: D

What is the solution set of

(A) {4} (B) {8} (C) {-4, 8} (D) {-8, 4} (E) {-2, ±2}

Correct Answer: D

During their daily training race, Carl has to stop to tie his shoes. Melissa, whose shoes are velcro, continues to run and gets 20 feet ahead of Carl. Melissa is running at a constant rate of 8 feet per second, and Carl starts running at a constant rate of 9.2 feet per second to catch up to Melissa. Which of the following equations, when solved for s, gives the number of seconds Carl will take to catch up to Melissa?

(F) 8s + 20 = 9.2s (G) 8s - 20 = 9.2s (H) (J) 8s = 20 (K) 9.2s = 20

Correct Answer: F