Answer:
20 visits
Explanation:
Each visit requires (1 volunteer)·(4 hour) = 4 volunteer·hour.
A 10-volunteer team working 8 hours has the resources to support ...
(10 volunteer)·(8 hour) = 80 volunteer·hour
So, the team can complete ...
(80 volunteer·hour)/(4 volunteer·hour/visit) = 20 visits . . . . each workday
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Conveniently, one volunteer can complete 2 4-hour visits in an 8-hour day, so 10 volunteers can complete 2·10 = 20 visits in an 8-hour day.