Cynthia was asked to subtract 0.223 from 0.54. Which of the following is the best estimate that cynthia can make to check her answer?

How do i do this? i don’t understand

Pyramid shown has a square base that is 18 inches on each side has a surface area of 164 square inches what is the slant height

Sue's average score for three bowling games was 162. in the second game, sue scored 10 less than in the first game. in the third game, she scored 13 less than in the second game. what was her score in the first game?