What is -3 = h + 8 divided by 2? (also, please show a solution as to how i could check to see if the answer is correct)

What is the length of the segment joining the points at (4,5) and (6,-2) round to the nearest tenth if necessary

What is the value of the expression below? (81^2)^1/8

Which approach to the theory-and-research cycle does the following sequence reflect: (1) specific observations suggest generalizations, (2) generalizations produce a tentative theory, (3) the theory is tested through the formation of hypotheses, and (4) hypotheses may provide suggestions for additional observations?