Pls help ASAPPpPppOoP

Square a has a side length of (2x-7) and square b has a side length of (-4x+18). how much bigger is the perimeter of square b than square a?and show all work! you so

Tony is charged $ 50 and additional $0.15 per miles for renting a car. a) represent the cost of renting a car with an equation, and the determine the cost if he drove it70 miles. b) what would be the cost of a car rental if the car was driven 250 miles? show work

Compute the standard deviation of the following set of data to the nearest whole number. 10, 10, 15, 20, 25