What is cross multiplication helpful is?

Ppcc assigned a story board on eg. ppcc. edu about a post-apocalyptic world called the books of wisdom. i was wondering if anyone had any advice on how to do well. also is there a way to change you name?

Explain how a credit card works when a customer makes a purchase

Suppose you live in location a, a part of the united states with a semiarid climate . you travel to location b, which is in a neighboring area . there you would find a humid continental climate. in which direction is location b likely to be , relative to location a? what is an explanation for the difference