Plz help! Right answer for 20 points. Wrong answers will be reported! Thanks!

The product of two negative rational numbers is always zero sometimes zero never zero

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

David leaves his house to go to school. he walks 200 meters west and 300 meters north. how far is david from his original starting point?