If clavin's steps start at 36 inches and get 80% longer each step how long is his 21st step

Idon’t understand this.. will someone ? will mark brainliest along with 20 points.

Which are factor pairs of 350? choose all answers that are correct. a) 30 and 12 b) 35 and 10 c) 70 and 5 d) 2 and 125

The clayton family’s pool has vertices at the coordinates (0, 2), (0, 5), (2, 5), (2, 6), (5, 6), (5, 1), (2, 1), and (2, 2). if each grid square has an area of 9 square feet, what is the area of the pool?