This was asked already
c=pid or
c=2pir
use first one
c=3pi
3pi=c=pid
3pi=pid
divide by pi
3=d
diameter=3 units
I'm assuming your answers are listed as 1 through 4, not decimals.
You simply take 12 - 8 = 4, but ten min. less than that, so 3 hr, 50 min. then add 3 hr 45 min, totaling 7 hr 35 min. , which is closest to 7 and 1/2 hours, the second option.
387
Hope this helped!!!!!
X = 5y + 30/4 - 3 is the answer.