clear
//find the brake thermal efficency of an engine
//given
w=16.2
t=20.
p=126.
q=19300.
//during 20 minutes period of the test 126 bhp for a period 1/3 hour 126*(1/3.)
btu=42.*2544.
hi=16.2*19300.
bth=(btu/hi)*100.
printf("\n \n brake thermal efficency %.2f percent",bth)