1- Would a research study on the effects of playing online games on children's cognitive development be considered a positive or normative statement?

2- 'Opportunity cost is both subjective and speculative. As such the concept of opportunity cost has no place in the scientific decision making process.' Discuss.

3- Critically assess the view that an understanding of the principles of 'scientific' decision-making is fundamental to the success of a modern economy

i need answers and resource or citation for each question