The Russians and Chinese have no problem with putting weapon systems in the hands of their women soldiers. One of their women soldiers will kill you just as dead as any of their male soldiers.
Depends on a lot. If they have to hump all their equipment for hundreds of miles, it's very unlikely there will be any of them around to shoot at male soldiers. If they are carried by others to the place where you are, then they might be able to do it.
Yes, women can fire a gun as well as a man, but there is a lot more to being a soldier than just firing a gun. You have to carry it to the point where you are going to fire it. When everything is easy, women can do it. When everything is difficult, the women will not be able to keep up.
We are fine having these weak links in our combat ranks so long as we greatly outclass any adversary. If we find ourselves in a conflict in which we have to face equal or superior forces, we will rue the day we poisoned our effectiveness for the sake of "social justice" preening.