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Johnny rode his bike to a friend's house 4 blocks down the street in his neighborhood. he immediately rode back home once he realized his friend was not able to play. what was his displacement for the total bike ride? how did you determine this? what could we use as a reference point to determine he was in motion during his bike ride? why can you use it as a reference point

Aremote community desperately needs more electrical energy. it is located in an area with the following characteristics: average wind speed of 15 – 20 km/hr some medium-sized rivers with slow-moving currents few coal deposits some oil exploration being conducted within 400 miles based on the above information, which energy source would be the most economical and safest for the community to pursue? a. fossil fuel b. hydroelectric c. nuclear d. wind

The function of the ciliary escalator is to