Chapter 7 - Exponents and Exponential Functions - 7-3 Multipying Powers with the Same Base - Practice and Problem-Solving Exercises - Page 430: 44

$a^{12}\times a^{0}=a^{12}$

$a^{12}\times a^{?}=a^{12}$ To multiply powers with the same base, we add the exponents. When we add $12$ and the second exponent, we must get $12$. The only way this is true is if the second exponent is $0$ because $12+0=12$. Therefore, $a^{12}\times a^{0}=a^{12}$