1.Let Un=n!(n+2)!U_n = \frac{n!}{(n+2)!}Un=(n+2)!n! where n∈Nn \in \mathbb{N}n∈N. If Sr=∑n=1rUnS_r = \sum_{n=1}^{r} U_nSr=∑n=1rUn, then limr→∞Sr\displaystyle \lim_{r \to \infty} S_rr→∞limSr equalsa.222b.111c.12\displaystyle \frac{1}{2}21d.Non existentLogin to continueOnly logged in users canattempt or see the solution.