world class speed skaters can skate a 3,000 meter course in about 4 minutes. what is their average speed for this course?

12.5 m/s.

v = d/t

(60 s/1 min)*(4 min) = 240 s

v = 3000 m/240 s  

v = 12.5 m/s  

when it gains or loses electrons

c because the action was the roller coaster reaches bottom of hill (action) reaction would be blood tends to drain away from head

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