$(3)(4pts)$ Use the given information $to$ rewrite the Riemann sum $so$ that the only variable

remaining $is"i."$ Fill $in$ the boxes below $to$ write the right$-$endpoint approximation, $R_{25},$

for the function $f(x)=\sqrt[\phantom{2}]{1+x^2}on$ the interval $4,10.$

$Do$ not simplify any parts. Your final answer should use the formula for $f(x)$ and the

formula for $x_i$ explicitly.

$R_{25}={\displaystyle \underset{i=1}{\overset{25}{}}}f(x_i)x=$

$R_{25}=,{\displaystyle \underset{?}{\overset{?}{}}}$