10 pennies fell on the floor. 2 of the pennies landed on heads. What is the theoretical probability of this happening?

Does anyone know how to do geometryme with this problem

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

Ebuka's monthly rent is $750. if ebuka pays the rent late, his landlord charges 4% interest per week that the payment is late. write a function that gives the total cost r(t), in dollars, of ebuka's rent if he pays it t weeks late.