QUES: They have a case with a screw back and a mineral crystal sapphire crystal that is both non reflective and scratch resistant

correct the punctuation.

CORRECTED: They have a case with a screw back, and a mineral crystal / sapphire crystal that is both non reflective and scratch resistant.

QUES: This is natural for the boldest steps forward were taken in a field which was long reserved for theoretical study which was promoted mainly and even almost exclusively in theory

correct the punctuation.

CORRECTED: This is natural, for the boldest steps forward were taken in a field which was long reserved for theoretical study, which was promoted mainly, and even almost exclusively, in theory.

QUES: Steering hydraulics Oil flow 308 lmin

correct the punctuation.

CORRECTED:
Steering hydraulics - Oil flow 30.8 l/min