If the ligament is replaced with one that has twice the diameter, by what factor does the restoring force increase

What’s #16 asking and how do i solve it?

In which situation is the acceleration of a car negative? question 5 options: a)the velocity of a car was 75 km/hr over 4 hours. b)the velocity of a car reduced from 50 km/hr over one minute. c)the velocity of a car increased from 40 km.h to 75 km/h over 15 minutes. d)the velocity of a car was 45 km/hr at 2: 00pm and at 4: 00pm its velocity was 85 km/ht.

Newtons view of arrangement of the universe. don't copy from anywhere.