Question

(scientific investigations) help please.

Answer 1

I agree with what you've chosen for question two and three.

I would choose C for the fourth question and argue that you shall also go with C for question five.

One of the main ideas about repetition is to have multiple Trials- or independent experiments- for a single independent variable using identical experimental setup. The table presented in option C is the only one among the four choices that allots spaces for measurements from multiple independent experiments.

Hypotheses are predictions of the outcome of a particular experiment. A hypothesis is correct only if it accurately describes the outcome of an experiment. The hypothesis, not the data, would have to be revised if the two doesn't fit. The researcher could keep developing and testing new hypotheses until arriving at a correct one.

Additionally, I would prefer option B over option D in the first question- responses to that question can depends on what your teacher says about the validity of different sources, given that neither B nor D are reliable as sources that one would like to cite in a paper.