Act 11.3 book page 143
A1 Is important to boil water to dry off any dissolved air.
A2 So that the yeast would not mix with the ahogar solution.
A3 To absorb the oxygen of the yeast.
A4It transport carbon dioxide from the yeast to the limewater.
A6 If you respire near the yeast tube you would change the experiment and have a variable.