I'm bored this summer and have interest in learning a new math. although i only have experience with algebra 1. does anyone have suggestions?

Prove that the value of the expression 7^8–7^7+7^6 is divisible by 43.

What is the measure of one interior angle of a pentagon

Hey hotel charges guests $19.75 a day to rent five video games at this rate which expression can be used to determine the charge for renting nine video games for one day at this hotel? pls