Help I don't understand I would be very grateful

On an airplane there are two seats on the left side and three seats on the right side there are 90 seats o the right side of the plane

Does anyone know how to do geometryme with this problem

The boiling point of water at an elevation of 0 feet is 212 degrees fahrenheit (°f). for every 1,000 feet of increase in elevation, the boiling point of water decreases by about 2°f. which of the following represents this relationship if b is the boiling point of water at an elevation of e thousand feet? a) e = 2b - 212 b) b = 2e - 212 c) e = -2b + 212 d) b = -2e + 212