Answer:
Step-by-step explanation:
F = 
mv² = Fr
m = 
5 balls = 3.1 pounds
1 ball = 3.1 ÷ 5 = 0.62 pounds
I would use the starting position, sea level as zero. Then I would convert all those minutes to hours so the answer is an integer and not a decimal.
60 min * (-10 ft / 212 min) = -2.83 ft/hr
round to integer = -3 ft/hr
Answer: The distance between them would be, (8,-5)
I think that this is right, but I assumed that the ceiling has the same dimensions as the wall you would need 4 gallons for 2 coats.
Work:
20x8= 160 (square feet for 1 wall)
160x5=800 (i assumed there are 4 walls and 1 ceiling)
800x2=1600 (you need 2 coats)
1600/400=4 (each gallon includes 400 square feet)
