If a person carrying water for the red heifer stops and rests, does this disqualify the water?
Halacha 1 rules that standing and resting does not disqualify the water — it is not considered 'work' in the relevant sense.
Question 2
If a person sanctifies water for himself and a colleague simultaneously, whose water is valid?
Halacha 4 rules that when sanctifying for both simultaneously, his own water is disqualified but his colleague's is acceptable.
Question 3
Two people agree: 'You sanctify water for me and I will sanctify for you.' What is the ruling?
Halacha 6 rules that this mutual arrangement disqualifies both waters — sanctifying as a 'worker' for another person is equivalent to receiving wages, which disqualifies sanctification.
Question 4
What if two people agree: 'Sanctify water for me and I will draw water for you'?
Halacha 7 rules both are acceptable — the exchange of drawing (not sanctifying) for sanctifying is permitted, since drawing is not subject to the wage-disqualification rule that applies to sanctification.
Question 5
May a person carry the key to the storage closet while going to sanctify water?
Halacha 8 permits carrying the key to the closet where the sanctification vessel is stored — this is considered an integral part of the sanctification process, not extraneous work.