Tell her to get a copy of "Parenting with Love and Logic" by Jim Fay and Foster Cline.
Meanwhile, she can just give up the clothing battle. Tell the girl to get dressed and let her choose whatever she wants. The kicker here is that even in kindergarten kids will notice (and comment) if a classmate is dressed weird. She will listen to them before she listens to her mother, then the decision to make different dressing choices will be her own. Another common morning battle might be that she takes too long to get dressed, then they're late for school, etc. Mom should state what time the car will leave and stick to it. The girl can choose to leave the house with her clothes on her body or her clothes in a bag. The catch is that MOM has picked out the clothes that are in the bag (they could be her least favorite outfit). Put the little darling in the car in her undies (yes, this might be kicking and screaming). Chances are she'll be dressed before she's out of the driveway. I did this with my 3 yr old about 4 months ago and haven't had a problem getting dressed in the morning since.
As far as the disrespectful talk, Mom needs to be sure the child isn't getting what she wants. She may have a tendency to give in just to shut the kid up, but that's only reinforcing her language.
The old fashioned bar of soap would be a good initial consequence.
She'll likely still do it, that's when you can give her the choice of "Would you like your mouth washed out with soap or would you like to go to your room until you can think of nicer words?"
A friend has been put her 5-yr-old in "time out from talking to mommy." Mom just ignores her, and when she gets really loud and disruptive she sends her away with something like "my ears can't hear you" or "This is not the place for yelling. If you need to yell, you can go to your room, or go to the back yard." Yes, the child may be screaming "I hate you" and "you're mean" all the way to her room, but mom just answers, "I know," every time.
The point is that when a child is speaking disrespectfully, she needs to be sent away because no one wants to hear it.