What do I do this is my lat question and I forgot how to do this

Translate the word phrase into a math expression. 15 fewer than the product of 4 and a number. (pls immediately)

1) in triangle the, what is the measure of angle t (in degrees)? 2) in triangle bat, the measure of angle b is 66∘, and the measure of angle t is 77∘.what is the measure of the exterior angle at a (in degrees)?

How many kilograms of a 5% salt solution and how many kilograms of a 15% salt solution must be mixed together to make 45kg of an 8% salt solution?