What is the explicit formula for the sequence 18, 9, 9/2, 9/4, 9/8

Pick the description of a geometric object that best matches the real world object box for a deck of card

Find the domain and range of the following function f(x) = 51x - 21+ 4

Non-euclidean geometry was discovered when, in seeking cleaner alternatives to the fifth postulate, it was found that the negation could also be true a. true b. false