A uniform plank AB of length 5 m and mass 22 kg rests horizontally in equilibrium on supports at C and D. AC = 1.7 m and CD = 2.5 m. Find the reaction on the plank at D. An object of mass 6 kg is now attached to the plank at A and equilibrium is maintained. Calculate the new reaction at C.

Arocket starts from rest and moves upward from the surface of the earth. for the first 10.0 s of its motion, the vertical acceleration of the rocket is given by ay = 12.80 m/s32t, where the +y-direction is upward. (a) what is the height of the rocket above the surface of the earth at t = 10.0 s? b) what is the speed of the rocket when it is 325 m above the surface of the earth?