Question 1177157
.
<pre>


It is the same as to ask 


    How many words of the length 40 can be made using 4 letters A, T, G or C.



We have 4 independent opportunities in every of 40 positions,

so the answer is  {{{4^40}}} = {{{2^80}}}  possible nucleotide sequences.
</pre>

Solved, answered and explained. And completed.