A baby bounces up and down in her crib. Her mass is 13.5 kg, and the crib mattress can be modeled as a light spring with force constant 594 N/m.

A baby bounces up and down in her crib. Her mass is 13.5 kg, and the crib mattress can be modeled as a light spring with force constant 594 N/m.(a) The baby soon learns to bounce with maximum amplitude and minimum effort by bending her knees at what frequency?(b) If she were to use the mattress as a trampoline—losing contact with it for part of each cycle—what minimum amplitude of oscillation does she require?