April swims 50 m north and then turns and swims 20 m back to the south.
what is her velocity if it takes her 60 seconds?

0.5 m/s north

Explanation:

Velocity is displacement over time.

v = Δx / Δt

Displacement is the difference between the final position and the initial position.  April swims 50 m north, then turns and swims 20 m south.  So her displacement is 30 m north.

v = (30 m north) / (60 s)

v = 0.5 m/s north

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-with the above experiment, the first geothermal plant in usa started in 1922 with a capacity of 250 kilowatts

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-in 1973, when oil crisis began many countries began looking for renewable energy sources and by 1980’s geothermal heat pumps (ghp) started gaining popularity in order to reduce heating and cooling costs

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hope this