LOL! Look closer at both the question and the photo, then count the money again. I already copped to having less than $50, and there's one bill there that's hidden under the one on top of it. Its denomination can't be verified.
The bill in question has a 98% probability of being a one.
1. the bills are stacked in descending order and separated to detail each separate denomination 2. all the bills of larger denomination are purposefully shown. When showing off money, one doesn't hide large denominations. One stacks low denominations under larger ones to make it look like they have more than they actually do. 3. the unseen bill is creased like the other ones, not the higher denominations. 4. while having 5 ones is a bit odd, note that the top bill is not only dog-eared, but is also facing the wrong direction. This indicates it was added later. (4 ones plus a fifth tossed on top for good measure)