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 inially occupying a volume of 1 m2 at 100 kpa, 27 c undergoes three internally reversible processes in series. process 1-2 compression to 500 kpa during which pv constant process 2-3 adiabatic expanslon to 100 kpa process 3-1: constant-pressure expansion to 100 kpa (a) calculate the change of entropy for each of the three processes. (b) calculate the heat and work involved in each process. (c) is this cycle a power cycle or refrigeration cycle?