(this is a plato question by the way)

blank 1: sulphur dioxide, methane, oxygen

blank 2: carbon monoxide, nitrogen, carbon dioxide

Blank 1 : Methane

Blank 2: Carbon dioxide

Explanation:

A rotting biomass would emit a huge proportion of methane. Microbes work on waste products and releases methane and other gases. Methane is the primary biogas obtained from a decaying biomass. Methane can be used as a source of fuel for both industrial and domestic purposes.

Burning of biomass would produce carbon dioxide to a large extent. Methane produced would fuel the burning process so as to release significant amount of carbon dioxide.