How do i find missing angle measures ? is there some formula ?

And employee salary increased by $4500 which represents a 15% raise what is the rate of the increase

Solve 3x-18=2y and 5x-6y=14 by elimination or substitution . show all !

Select the margin of error that corresponds to the sample mean that corresponds to each population: a population mean of 360, a standard deviation of 4, and a margin of error of 2.5%