Can someone help me with my homework? (I need to show my work btw)

here’s the question :

At the Pokemart, you bought 3 potions for $20 and 1
revival for $80. How did the withdrawals change the
amount in your account?

Lindsay used two points, (x,y; ) and (+2.82), to find the equation of the line, y = mx + b, that passes through the points. y2-y, first, she used the definition of slope and determined that the value of mis x, - . given this information, which expression must represent the value of b?

Ijust need to see how to do this. so you don’t have to answer all of them just a step by step explanation of one.

The circumference of a redwood tree trunk is 20π ft, and it is 100 ft tall. what is the approximate volume of the redwood tree trunk? 1,000π ft3 10,000π ft3 4,000π ft3 40,000π ft3