Being the common layman, we tend to use words fairly loosely, and when one is not an expert at something, it's just easy to do so. And the rest of the non-experts accept the use of many terms which technically aren't accurate. Wasps, hornets, yellow-jackets ... these are all terms that have specific entomological meaning, but are lost on Joe Average.
But technically, to answer the OPs question, it would be too hard to tell from the photo (not enough clarity and detail) to tell what insect sub-species that are in the photo. There are literally thousands of distinctly different stinging insects that would resemble what we would colloquially call a "wasp" or a "hornet" in the US alone. According to the video linked below, there are something like 30,000 types of bees/wasps/hornets worldwide. So identifying the flying insects in that photo is gonna be pretty tough from a single photo at distance.
The term "wasp" is an over-arching classification of a type of insects, and "hornets" are a subclass. All hornets are wasps, but not all wasps are hornets. It also doesn't help that the "bald faced hornet" actually isn't a hornet at all, but it is a wasp ... So even the common names of some of these insects are misleading.
Here's a quick viewpoint:
https://www.thespruce.com/hornet-vs-wasp-7376280
Search this on YT "
What is the Difference Between Bees, Wasps, and Hornets?"
It's a rudimentary look at the topic, but does back up what I am trying to explain.
(technically, there is a slightly profane word in the video, and so by our rules I cannot post the link here; it's pretty benign and safe for even kids to watch ....)
As for killing the insects, I take no stand one way or another. Regarding ground-based nests, I will say that using gasoline, while effective, isn't environmentally sound. It's actually quite easy to use a mix of water and liquid dish soap. Always do this at night, when they are less active and can't see well. Both the dish soap and gasoline kill them by the same means, though by slightly different methodology. Dish soap is a lot cheaper, more safe for the environment, and just as easy to use. Also, all the "methrin" chemical products are effective at killing insects, but at different rates; these come in liquid or powder forms, and need to be handled carefully. These are often the main ingredient in the retail spray can insecticides. (deltamethrin, permethrin, cypermethrin ...).