Question

How many different types of polypeptide can be constructed from just 5 amino acids

Answer 1

Few of the Many Possible Polypeptide Chains Will Be Useful
For a typical protein length of about 300 amino acids, more than 10390 (20300) different polypeptide chains could theoretically be made.

Answer 2

i think its 5×5×5×5×5 According to the permutation formula in mathematics