What is 3.8 as a repeating decimal as a fraction

If 90° < θ < 180° and cotθ = -1/3, then cscθ =

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?

Adesigner charges a one time fee of $200 plus $40 an hour for each project. write an expression to represent how much money the designer will make for a project