Yea the bowl its a dogs bowl LOL
Gitta think though Luff's 15lbs of muscle doomtown lol
1. It depends on the cat.. Some cats won't try and jump, some for some reason love death-defying heights(mine included). Three floors is pretty high though, so I would think you're safe.. My cat used to jump from our second floor balcony to get out-she did this regularly and without causing harm to herself.. My ex's cat would also climb a tree 40-60 feet in the air and "hang out" for a few days before coming down-one way or another, and again, unharmed.. You'd be amazed how much impact they absorb from a jump/fall.
If you had cement at the bottom I would say no way, but you said you have plants.. Bushes would provide some cushion if she were to jump.
2.lol, I had the same problem.. Try either a bigger stone fountain(natural running water, and heavy) or a large ceramic DOG bowl.. too heavy for him to tip over.