Choose the right variant.

1. Euclid brought together all the geometrical laws known at that time and arranged them into:
   •  a deductive system
   •  an axiomatic system
   •  a computer system
2. In any deductive system certain propositions callled theorems are proven or deduced:
   •  very rapidly
   •  much better
   •  step by step
3. The postulates themselves cannot be proven since they are:
   •  theorems
   •  the propositions which we take as our first premises
   •  axioms
4. The first definitions must define terms by using:
   •  formula
   •  other terms
   •  Pythagorean theorem
5. Euclid considered that the postulates and definitions are:
   •  absolutely certain self-evident truths
   •  word combinations
   •  falsifications