Hey plz solve this question I will mark as the brillianest plz

The position of a crate sliding down a ramp is given by x=(0.05t^3) m, y=(1.7t^2) m, z=(6−0.85t^5/2) m, where t is in seconds. (a) determine the magnitude of the crate's velocity when t = 2 s. (b) determine the magnitude of the crate's acceleration when t = 2 s.

Find the magnetic field a distance r from the center of a long wire that has radius a and carries a uniform current per unit area j in the positive z direction.

The electric field between square plates of a parallel-plate capacitor has magnitude e. the potential across the plates is maintained with constant voltage by a battery as they are pulled apart to twice their original separation, which is small compared to the dimensions of the plates. the magnitude of the electric field between the plates is now equal to a)e b)e/4 c)e/2 d)4e e)2e