Some plz plz me i don't understand

Clarence wants to buy a new car. he finds an ad for a car that costs 27,200 dollars. suppose his local sales tax is 7%. -how much would he have to pay? -what is the cost of the car including tax? -if clarence has 29,864 saved, can he pay cash to buy the car?

The function f(x)= x5+ ( x + 3)2 is used to create a table. if x = -1 then what is f(x)?

If bradley saves for 4 weeks, what is the total amount of money he will have saved?