THE ONLY DISADVANTAGE OF USING BIOGAS IS THAT IT IS...A. COSTLY B....

37. - 6 MÃ ĐỀ AV HK 2 12CB
6 MÃ ĐỀ AV HK 2 12CB

37.

The only disadvantage of using biogas is that it is...

A.

costly

B.

clean to the environment

C.

smoke-free

D.

available