21. A water main is to be designed to serve a proposed 100-home residential subdivision on 50 acres. Which of the following
a) the required fire flow is nearly the same as the average day demand
b) the required fire ſlow is between 2 times and 5 times the average day
demand
c) the required fire flow is between 5 times and 100 times the average de
demand
d) the required fire flow is more than 100 times average day
demand

Air at a pressure of 1atm and a temperature of 40 c is in parallel flow over the top surface of a flat plate that is heated to a uniform temperature of 120 c. the plate has a length of 0.40m (in the flow direction) and a width of 0.15m. the reynolds number based on the plate length is 50, 000. what is the rate of heat transfer from the plate to the air? if the free stream velocity of the air is doubled and the pressure is increased to 10 atm what is the rate of heat transfer?