Answer:
a
The condensed structural formula for methane is

b
The condensed structural formula for ethane is

c
The condensed structural formula for pentane is
d
The diagram for the structural formula for cyclopropane is shown on the first uploaded image
Explanation:
Answer:ummm 45
Explanation: I feel like im sure of it
Answer:
copper
Explanation:
coal, petroleum, and natural gas are all related to fossil fuels.