The U$.$S$.$ Treasury is auctioning $$10$ billion in $13-$week Treasury bills. The following bids were submitted:

$$Bidder

Bid Amount $($$ billion$)$

Yield Requested $(\%)$

$$A

$3$

$4\mathrm{.}5$

$$B

$4$

$4\mathrm{.}55$

$$C

$2$

$4\mathrm{.}6$

$$D

$3$

$4\mathrm{.}65$

$$E

$2$

$($Non$-$Competitive$)$

What is the stop$-$out yield? You need to describe how you get the stop$-$out yield. $($Note: Each non$-$competitive bid is limited to $$10$M$,$ but the total amount from various bidders could exceed $$10$m$)$