Output voltage between the fixed type and the adjustable type.

I'm selecting LDO now .

When I look at ADP1710 and ADP160/1 datasheet, I've got something to make sure about some specification.
Is anyone help me to figure out?

No1,  In ADP1710's fixed output type ,  its output accuracy is specified at ±2% in the condition. Line regulation is not inculuded,right?

No2, ADP1710's Adjustable output is 0.8V basis. I think it's a reference voltage of the error amp. But I wonder why the fixed type generate 0.75V out put.

No3, what's the ADP160/1 reference voltage of the error amp?

I'm a little bit confused about the minimum output voltage between the fixed type and the adjustable type.