Which season? For bow season......absolutely. I hunt cows very similarly as I do bulls.......with my bugle. But regardless what you use, you still want to know what you're doing with them and why.
Definitely! I cow call when walking through the woods and have also called cows into wallows. They get curious.
Another technique when we've bumped a herd that scatters but they didn't get a good sight/smell of us is a frantic lost calf call. They'll come back highly alert so drop back and put your friend in front of you 30-40 yards to make the shot
Probably more effective for cows than for bulls honestly. Esp during early fall- cows are still curious. Bulls are on guard and protective, often take the herd and head away from calls to protect their harem.