Suppose that the number of A's per thousand increases linearly from 200 at one end of the DNA strand to 250 at the other. The number of C's per thousand increases linearly from 250 at one end to 300 at the other, and the number of G's per thousand decreases linearly from 300 at one end to 200 at the other. The remainder is made up of T's.
A piece of E. coli DNA has about 4.7 × 106 nucleotides, and is about 1.6 × 106 nm long. The genetic code consists of four possible nucleotides, called A, C, G, and T. For each of the following cases,
a. Use the given information to find the formula for the number of A's, C's, G's and T's per thousand as a function of distance along the DNA strand.
b. Find the total number of A's, C's, G's, and T's in the DNA.
c. Find the mean number of A's, C's, G's, and T's in the DNA per thousand.