I need help here with explanation pleas

How do you use the elimination method for this question? explain, because i really want to understand!

Someone answer asap for ! 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

Round each decimal to the nearest thousandth. a. 5.39562 b. 0.12345 c. 5634 d. 18.93763