1) Can a car take a battery with more Cold Cranking Amps than designed for?
My car battery is rated at 550 CCA and I've seen batteries for my car that can go up to 700 CCA.
2) Can a battery with higher CCA's last longer than one with less CCA's?
1) Can a car take a battery with more Cold Cranking Amps than designed for?
The main thing is the battery size. So as long as the size matches, you can use whatever CCA battery you like.
2) Can a battery with higher CCA's last longer than one with less CCA's?
Yes.
1) Can a car take a battery with more Cold Cranking Amps than designed for?
That's just a rating. The battery will only work as hard as the starter motor needs.
It's the same as using a 5 ton jack to lift a one ton vehicle. (it'll work fine, but your jack is unnecessarily big and heavy)
2) Can a battery with higher CCA's last longer than one with less CCA's?
Not really.
But a battery with higher RC (Reserve capacity) might.
A battery with higher RC (Reserve capacity) ? Would you be to explain that to me? What types and brands when I'm shopping and how does those systems work?