PLZ help Quick im in a test

Use set buikder notation to represent the following set: {, -2, -1, 0}

Write 17/20 as a decimal and as a percent.

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?