JEE Main Physics question

A roller coaster is designed such that riders experience "weightlessness" as they go round the top of a hill whose radius of curvature is 20 m. The speed of the car at the top of the hill is between

• (A)16 m/s and 17 m/s
• (B)13 m/s and 14 m/s
• (C)15 m/s and 16 m/s
• (D)14 m/s and 15 m/sCorrect