Got this from Google hope this helps
The monomers of DNA and RNA are nucleotides, which are made up of a phosphate group, a five-carbon sugar and a nitrogenous base<span>. In DNA, the </span>nitrogenous bases<span>are </span>adenine<span>, </span>cytosine<span>, guanine and </span>thymine<span>. In RNA, the </span>nitrogenous bases<span> are</span>adenine<span>, guanine, </span>cytosine<span> and </span>uracil<span>.</span>
Answer:
A.The hole in the ozone layer
Explanation:
• Montreal protocol is an international treaty that was signed to control the use of substances that are resulting in the depletion of the ozone hole.
This treaty was signed in the year 1987 and became effective form 1989.
• Since the time that this treaty has come into force, there has been a significant improvement in the ozone hole that was observed over Antarctic as it's size has decreased.
• This improvement has been possible because the treaty helped to phase out chemicals such as chlorofluorocarbons, carbon tetrachloride, etc. that are responsible for ozone hole depletion.
Mostly during the summer, July would be the best month to see them.
Gametes
gametes is another word for sex cells
