Solve for x, y, and z please

Julius sold five times as many computers as sam sold last year. in total, they sold 78 computers. how many computers did julius sell?

Cot(90° − x) = 1 the value of x that satisfies this equation is °. a. 60 b. 135 c. 225 d. 315

Atotal of 766 tickets were sold for the school play. they were either adult tickets or student tickets. there were 66 more student tickets sold than adult tickets. how many adult tickets were sold?