Please help me Tell me which strip should he use ? And why? Find LCD

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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)

Aubrey read 29 books and eli read 52 books what number is equal to the number of books aubrey read?

Jim had 15 minutes to do 5 laps around his school what would his time be