I have been clearing brush by a lake in northwest Missouri and seen a lot of dragonflies. It's hard to get decent pictures because my phone camera sucks and they fly away before I get close. But here is one I managed to get:
The overall body shape of the second dragonfly looks like a Libellula (Skimmer), due to its broad flat abdomen. It also seems to have distinct bands on all four wings, dark patches where the wings connect and a light blue abdomen, which would indicate e.g. a male Plathemis/Libellula lydia (Common whitetail). The picture is blurry though, and there might be other similar species that it can be mistaken for (the wiki page mentions a couple of similar species).
The first one is a blue dasher (Pachydiplax longipennis).
Sorry, I couldn't identify the second one but it is more probably the same.