Find missing angle of triangle 63 61 and b

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?

Which of the following points is collinear with (-2,1) and (0,3)

If a is a nonzero real number then the reciprocal of a is