#### Answer

$(b^{2})^{4}=b^{8}$

#### Work Step by Step

$(b^{2})^{?}=b^{8}$
To raise a power to a power, we multiply the exponents. Therefore, in order for this equation to be correct, the product of two and the second exponent must equal $8$. The only way this would work is if the second exponent is $4$ because $2\times4=8$.
Therefore, the correct equation is $(b^{2})^{4}=b^{8}$