Q1.1
The process has already begun with an observation -- your friend did not show. Now you must formulate a hypothesis that tries to explain your observation: "My friend never saw the note." Next you must devise an experiment to test the hypothesis: go to where you left the note and see if it is still there.
Now this experiment is not definitive. Your friend may have read the note and left it in place -- implausible but possible. The wind may have blown the note away.
But that is what science is like. We come up with the best hypothesis we can, test it as best we can, and develop what seems like the best theory to explain our observations.
Q1.2
Q1.8
P1.2
P1.3
P1.4
P1.5
P1.6
P1.7
P1.8
C1.1
