Answer:
I don't know about the oil part but "It is important to develop alternative
sources of energy because scientists are unsure of how long they will last"
Explanation:
Because they are nonrenewable resources, it takes hundreds to millions of years for them to be made again naturally. Once we're out, we're out. It would be a huge issue of that happened because Oil, Petroleum, and Natural Gas (all fossil fuels) are needed for heating, gas stoves, etc.
Answer:
300,000km is the speed of light
The chemical make-up changes.
Out of the options, "Iron" is the most dense here.
In short, Your Answer would be Option D
Hope this helps!
