Can someone plz help me pretty plz

Write an expression that has three terms and simplifies to 4x - 7. identify the coefficient(s) and constant(s) in your expression

Abacteria population is tripling every hour. by what factor does the population change in 1/2 hour? select all that apply

The marked price of an article is 25% above its selling price and the cost price is 30% less than its marked price . find the discount percent and gain percent. only a brainlest can solve it i will mark you brainlest