Answer:
Hypothesis
perceivable and measurable
Thinking critically
Introspection
Step-by-step explanation:
A hypothesis acts as the premise or basis of experiment
It is like a guess that should return be proven right or wrong by the experiment
A scientific test must be perceivable and measurable such that it should be something that is tangible and can be measured such that it can be proven
Char is thinking critically by analysing facts to form judgement
Wilhelm is known as the father of experimental psychology and believed instrospection could be applied to reveal one's consciousness