Which of the following is correct about Bio-gas?

1.Bio-gas contains large amounts of methane.
2.It is a renewable source of energy.
3.Bio-gas normally burns without smoke and has a high heating capacity.

Select the correct answer using the codes below.

Bio-gas contains up to 75% methane.
It burns without smoke, leaves no residue like ash in wood, charcoal and coal burning. Its heating capacity is high. Bio-gas is also used for lighting.
The large-scale utilisation of bio-waste and sewage material provides a safe and efficient method of waste- disposal besides supplying energy and manure

By: kamaljeet kaur