(sec 12a - 1)/(sec 6a -1) = tan 12a / tan 3a

Jennifer taking a quiz and has answered 13 questions so far. if there are 25 questions on jennifer test, how many questions does she have left to answer

The center on a target has a diameter of 5 inches. the whole target has a diameter of 25 inches. complete the explanation for what part of the whole target is the center. the center of the target takes up % of the whole target.

How many four digit even numbers can be formed from digits 1,2,3,4,5 if repetition is allowed. how can solve this using permutation formula