Author Question: Because natural gas is odorless, a substance known as _______________ , which smells like rotten ... (Read 42 times)

frankwu · **on:** Jul 21, 2018

Because natural gas is odorless, a substance known as _______________ , which smells like rotten egg, is added to the natural gas to help detect leaks.

Fill in the blank(s) with the appropriate word(s).

Question 2

Natural gas is the cleanest burning of the fossil fuels and its combustion produces about _______________ percent less carbon dioxide compared to burning petroleum based fuels.

Fill in the blank(s) with the appropriate word(s).