From the rear, front, and left side. If approaching a vehicle from the right side while parallel parked it means you've parked illegaly facing on coming traffic.
It should be seen as both, but depending on the culture it may be more one than the other.
Whichever way gravity will tend to take the vehicle OUT of the roadway if the brakes should fail.
About 12".
if you parking uphill you turn your wheel towards the curb and if you parking down hill you turn it away
Donald Shoup on the High Cost of Free Parking
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