a car is traveling north on the interstate. They cover 645 miles in 9 hours. What is the car's average velocity ?

How much energy must a refrigerator absorb from 225 g of water so that the temperature of the water will drop from 35°c to 5°c

The number of passengers who arrive at the platform of a subway station for the 10 am train is a random variable with a mean of 120 and a variance of 16. find the lower bound of the probability that there will be between 100 and 140 passengers (round off to second decimal place).

What is the freezing point of radiator fluid that is 50% antifreeze by mass? kf for water is 1.86 ∘c/m.