Tony have 48 marbles he had 4 bags he wanted to know how to put all 48 marbles in for in the four bags

Will mark brainliest question in the pic.

Np4=12np2 with clear explanation.

How do i start to solve? would appreciate a walk-thru! a bird sitting 16ft above the ground in an apple tree dislodges an apple. after how many seconds does the apple land on the ground? (assuming that no branches will interfere with it's fall)