9. The protein-coding strand of the average human gene consists of 1,350 nucleotides. Assuming that each nucleotide can take any of four values (A, T, C, or G), how many different genes with exactly 1,350 nucleotides are possible? 10. Refer to the previous problem. Assuming that gene strands can have between 1,200 and 1,500 nucleotides, write an expression for the number of possible genes. (Don't bother trying to evaluate this expression!)