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dezoksy [38]
3 years ago
5

David rowed a boat upstream for three miles and then returned to point he started from. The entire journey took four hours. The

speed of the stream is one mile per hour. Find David's speed in still water. (Hint: speed = distance ÷ time, upstream speed = speed of the boat – speed of the stream, and downstream speed = speed of the boat + speed of the stream)
David's speed in still water is ____ miles per hour.
Physics
1 answer:
frez [133]3 years ago
4 0
Upstream speed = S - 1
Downstream speed = S + 1

Average speed = total distance / total time

Average speed = (S - 1) + (S + 1) / 2
= S

S = 6 miles / 4 hours
S = 1.5 miles per hour
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A scuba diver's tank contains 0.240 kg of o2 compressed into a volume of 3.10 l. what volume (in liters) would this oxygen occup
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