Find inequalities that describe a hollow ball with diameter 100 cm and thickness 0.4 cm. (Assume the ball is centered at the origin of the coordinate system.)
99.6 ≤ 𝜌 ≤ 100, 0 ≤ 𝜃 ≤ 2𝜋, 0 ≤ 𝜑 ≤ 𝜋
49.6 ≤ 𝜌 ≤ 50, 0 ≤ 𝜃 ≤ 2𝜋, 0 ≤ 𝜑 ≤ 𝜋
99.6 ≤ 𝜌 ≤ 100, 𝜋 ≤ 𝜃 ≤ 2𝜋, 0 ≤ 𝜑 ≤ 𝜋/2
0.4 ≤ 𝜌 ≤ 50, 0 ≤ 𝜃 ≤ 𝜋, 0 ≤ 𝜑 ≤ 𝜋/2
49.6 ≤ 𝜌 ≤ 50, 𝜋 ≤ 𝜃 ≤ 2𝜋, 0≤ 𝜑 ≤ 𝜋/2
(b)
Suppose the ball is cut in half. Write inequalities that describe one of the halves. (Select all that apply.)