A 5.50 kg crate is suspended from the end of a short vertical rope of negligible mass. An upward force F(t) is applied to the end of the rope, and the height of the crate above its initial position is given by y(t) = (2.80 m/s)t + (0.610 m/s³)t³ Part A What is the magnitude of the force F when t = 4.00 s ? Express your answer with the appropriate units.

I need help with part b. I think I have the answer but I'd like to double check part a and b.

How would i do part A? and what is it asking?

Two planes take off at the same time from an airport. The first plane is flying at 210 miles per hour on a bearing of S 45.0° E. The second plane is flying in the direction S 45.0°W at 250 miles per hour. If there are no wind currents blowing, how far apart are they after 4 hours? (Round your answer to two decimal places.) mi What is the bearing of the second plane from the first after 4 hours? (Round your answer to one decimal place.) S ° W

Which one I should choose exactly?

unit for radius of gyration?

Write the equation of the height of a river on each of the following Ferris Wheels, t, seconds after the rider passes the farthest right position

Can you answer question 1 part d?