Estimate the each part given problem:

Problem: An air-track glider of mass 0.100 kg is attached to the end of a horizontal air track by a spring with force constant 20.0 N/m. Initially the spring is unstressed and the glider is moving at 1.50 m/s to the right. With the air track turned off, the coefficient of kinetic friction is uk=0.47.

Part 1: How large would the coefficient of static friction have to be to keep the glider from springing back to the left when it stops instantaneously?

Part 2: If the coefficient of static friction between the glider and the track is ?s= 0.80, what is the maximum initial speed v1 that the glider can be given and still remain at rest after it stops instantaneously?

I need help to solve the above problem and express your answer giving two significant figures.