As always, some answers and numbers will change depending on your locality.  Also, that sheet to track bagger times doing tasks is not a manditory form, at least not here.  I have seen it, but nobody has ever filled one out.

A1.  They are supposed to swap cart pushers out for that very reason, however it will not always be carried out.  Personally, if I get too tired I just come in, let them know, and ask if they want me to send out the next person.  If it is extremely hot or cold, there is about a 15-30 minute window they are supposed to have someone out before swapping cart pushers. Assuming all carts are out in the lot (happens far too often) and we are not busy, I can clear the lot in 45 minutes.  If you are super busy, you need someone pulling carts at all times just so you do not run out, and may need two people to actually clear the lot.  Buy a cheap watch, time yourself.  You cannot rely on others to keep track.  My supervisior usually doesn't even know who she just sent out to do carts five minutes after she told them.

That said, I have cart pushed for eight hours solid at one point, stopping only for breaks and lunch.  That will indeed murder your feet.  Better shoes are a must, but you don't need to spend big bucks.  Find some nice, solidly built work shoes at the local shoe store that claim to be work shoes.  Mine were about 30-40 dollars, and have held up very well.  That said, if you are going to do this for long, look into some insoles as well.  Either athletic or work insoles should do the trick, but it seems that athletic ones hold up a little better for heavy cart pushing work.  Even if they are not ultra comfortable to just walk around in, they can really take the pain away at the end of the day.  You may want to rub your feet when you get home some instead of just sitting down and relaxing.  In all though, the more you push carts, the less strain it will be.

Do not start pushing in only three or four at a time unless you absolutely must.  This will likely earn you some enemies among the other baggers and the people supervising you.  I reccomend that you see if you have a cart pulling strap, I think they are required to have them.  At least in my area, we are required to use them as part of our saftey agreements, but I am the only one who actually does so.  I find that it saves a lot of strain on my back because it keeps the carts together and helps make turning a row of carts easier.  I have seen some of the more scrawny girls have a much easier time pulling in six carts at a time when they used the strap.  Hook the metal end on the far car, on the bar parallel to the handle of the cart  Wrap the velcro end around the handle of the cart you are actually pushing from.

Find out how many carts you are allowed to pull in at a time.  There should be a number, in my area the number is six.  If your supervisor tells you something like "as many as you can manage" this is probably the wrong answer, you will want to check with whomever is involved in the store cultural council or whatever saftey program kroger has set up at your store.  Management cares about this, and upper management has given my managers a load of crap about this rule if not followed.

Also, always wear the yellow vest.  Always.  I have been backed into, and that yellow vest probably helped a little bit in them seeing me in time to not back over me completely.

Push carts in the middle of the road.  Sounds dumb and rude at first, but you do not want people backing into the row of carts because it was too close to their car and could not see it in the rear view mirror.  This helps cover you for liability and prevents a crappy day.  This gives everyone the best change to not hit the pile of metal you are moving.

2A.  There is no real protocol for dealing with this problem.  Ask them if they want their meat in a plastic bag before going in their bag.  A lot of folks are happy with that solution to prevent leaks.  Other than that, just don't smash or damage anything like normal, and keep cold with cold.  I generally ask reusable bag people how they want things done, because each one seems to have some particular way they want it done.

3A. Frankly, do not worry about it.  We get paid little, and after taxes we are still paid little.  Just do some math when you get your pay stub if you need a solid number.

A word of warning, I am assuming that you are a new hire, and that this is probably your first job.  Not saying that Kroger is the worst job on Earth, but this is not a place you want to stay too long.  Your store may be different from the rest of them I have seen and heard of, but Kroger can wear on you.  I recommend looking for a better job while you are working at Kroger.  Kroger is a good way to get some job experience, but you either want to be here as little time as possible or make a life career out of it for the benefits.

Pay raises are five cents every six months, and for baggers the pay cap is $7.35.

If you live somewhere that gets real cold in the winter, get a knit hat, earmuffs, gloves, scarf and boots.  My store provides a jacket and that is all for winter.