Zip codes in the us consist of 5 numbers. how many zip codes are possible if there are no restrictions on which the numbers can be used?

A20? -foot ladder is placed against a vertical wall of a? building, with the bottom of the ladder standing on level ground 19 feet from the base of the building. how high up the wall does the ladder? reach?

Ijust need to see how to do this. so you don’t have to answer all of them just a step by step explanation of one.

What is the quotient of m^6/5 ÷ 5/m^2? assume m does not equal pl