Homework Solution

TP 17-3

Given:

kitchen stove uses approximately 50 ft3/day of natural gas

from p. 554 of text: in Kenya 0.75 m3/day of biogas is provided from the manure of 2 cows

Find:

number of cows to furnish gas for 1 day for kitchen stove

Science:

units conversion

Solve:

biogas/day from 1 cow = (0.75 m3/day)/2 = 0.375 m3/day

1 m3 = (3.20808 ft)3 = 35.3 ft3

biogas/day from 1 cow = (0.375 m3/day)(35.3 ft3/m3)

biogas/day from 1 cow = 13.24 ft3/day

number of cows = (50 ft3/day)/(13.24 ft3/day/cow) = 3.78

I suggest 4 cows ANS