The first term of an A.P. of \( 30 \) non-negative terms is \( \frac{10}{3} \). If the sum of this A.P. is the cube of its last term, then its common difference is:
\( \frac{5}{87} \)
\( \frac{25}{83} \)
\( \frac{15}{29} \)
\( \frac{5}{29} \)