4xsquared 12x 10 is less than or equal to 0 (or what multiplies to get 40 and adds to get 12)

Write a numerical expression that satisfies all of the following conditions. 1.)the only number used in the expression is 5 2.)at least one exponent other than 1 is used 3.)when the expression is evaluated, the answer is greater than 40 and less than 50

1. the wheeling bridge in west virginia is about 307 meters long. if you walk with a stride of about meter, about how many steps would it take you to cross this suspension bridge?

Simplify the expression. -2/5(10+15m-20n)