[tex]a = ( \frac{ - 1}{5} ) {}^{5} \times {( \frac{ - 1}{25}) }^{8} = {( \frac{ - 1}{5}) }^{5} \times {( \frac{ - 1}{5}) }^{16} = ( { \frac{ - 1}{5} )}^{21} [/tex]
[tex]d = \frac{4}{( \frac{1}{8}) {}^{5} } = 4 \times {8}^{5} = {2}^{2} \times {2}^{15} = {2}^{17} [/tex]
