2) This is depending on the op amp you use and on your supply voltage.
There are op amps where the maximum output voltage range is smaller than their supply voltage, otherwise you'll get distortions (e.g. the ageing 741). Also there are op amps where the maximum output voltage range can be almost the same than their supply voltage range (called rail-to-rail op amps) and (but not used that often) "Beyond-the-rails" op amps, where the maximum output voltage range can be bigger than their supply voltage range.