Answer:
5 bases
Explanation:
If there are 17 amino acids and only 2 bases that can be combined in order to make a codon then:
for 4 bases 
is 16 and it is not enough combination for all 17 amino acids
for 5 bases 
is 25 combinations (meaning that more than one codon could code for the same amino acid).
A prothallium, or prothallus<span> is usually the </span>gametophyte<span> stage in the life of a </span>fern<span> or other pteridophyte. Occasionally the term is also used to describe the young </span>gametophyte<span> of a liverwort or peat moss as well.</span>
Three variables can be used .
1. Sun 2. Moon 3. Earth
These are suggestions that lizzie can control:
1.<span> Discover how long the Earth takes to orbit the Sun
2. how many hours it takes the Earth to spin around once on its own axis, 3. how long the Moon takes to orbit the Earth</span>
