Write the value $of$ each $limit.$ Round $to$ five decimal places $if$ necessary and include the

leading zero. $If$ the sequence $or$ series diverges $or$ there $isno$ way $to$ compute the exact

$limit,$ answer two zeros: $"00".$

$(a)(3$ points$)\underset{n}{lim}{\displaystyle \underset{0}{\overset{1}{}}}\frac{lnx}{\sqrt[n]{x}}dx$

$(b)$ points$\underset{n}{lim}arctan(\frac{n^4+7n}{(n^2+4{)}^2})=$

$(c)(3$ points$)$ For each $n,$ let $R_{n}be$ the region bounded $byy=3x-4,x=n,y=0$

and define the sequence $\{a_n\}by{a}_n=$ the volume with base $R_n$ and cross sections

parallel $to$ the $y-$axis are rectangles with height $\frac{1}{x^3}$

$\underset{n}{lim}{a}_n=$

$(d)(3$ points$){\displaystyle \underset{n=1}{\overset{}{}}}\frac{(-1{)}^{n+2}{2}^{3n}}{5^{\frac{n}{2}}{3}^{n+1}}=$