16. In the calculation shown, how many times does the term $2018^{2}$ appear inside the square root to make the calculation correct?
$$
\sqrt{2018^{2}+2018^{2}+\ldots+2018^{2}}=2018^{10}
$$

A 5
B 8
C 18
D $2018^{8}$
E $2018^{18}$
16. E Square both sides to get $2018^{2}+2018^{2}+\ldots+2018^{2}=2018^{20}$.
Let $n$ be the number of occurrences of $2018^{2}$. Then we get $2018^{2} \times n=2018^{20}$.
So $n=\frac{2018^{20}}{2018^{2}}=2018^{18}$.