Question

восьмой номер, срочно

Answer 1

b*-12 x b*15. 2*-12 x 2*15 = 2*3 = 8

* знак степени

Answer 2

$\displaystyle\bf\\\\\\b^{-12} \cdot(b^{3} )^{5}=b^{-12} \cdot b^{15} =b^{-12+15} =b^{3} \\\\b=2\\\\b^{3} =2^{3} =8\\\\Otvet:\boxed8$