Marks test scores for this semester were 83,80,91,74,66,95,87,72,95,97 what is the mode of his test scores

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)

Due to a packaging error, 4 cans labeled diet soda were accidentally filled with regular soda and placed in a 12 pack carton of diet soda. two cans were randomly selected from this 12 pack. what is the probability that both cans were regular soda?

Find the amount of simple interest earned for depositing the given principle in an account if $2200 is invested at 5.5 % for 6 months