Given the following information:

ES for $3-6$ is $15$ days and ES for $4-6$ is $32$ days.

The expected activity times are $22$ days for $3-6,9$ days for $4-6,$ and $7$ days for $6-7.$

$($Hint: draw the network and complete a FW pass$)$

What is the ES for activity $6-7?$

$15$

$41$

$32$

$37$

$48$