Help me with this please

What are the domain and range of f(x)=[1/5]x

Big boi and travis scott are performing at the super bowl. travis scott is 62 years younger than twice big boi’s age. the sum of their ages is 70 years old. use b to represent big boi’s age. write and solve an equation.

Dakota earned $7.50 in interest in account a and $18.75 in interest in account b after 15 months. if the simple interest rate is 4% for account a and 5% for account b, which account has the greater principal? explain. to make it a little easier, there is an image. good luck!