Why should Mike repeat this investigation? Mike needs to make sure that all the skateboards are not affected by friction.
Mike needs to have more than one set of numbers to make an accurate graph
The investigation needs multiple trials to determine which board is the control.
The investigation needs to be repeated several times to have the most accurate data.

D

Explanation:

the small 0.38-kg slider is known to move from position a to position b along the vertical-plane slot. determine (a) the work done on the body by its weight and (b) the work done on the body by the spring. the distance r = 0.70 m, the spring modulus k = 154 n/m, and the unstretched length of the spring is 0.53 m

explanation:

-reverse card

r = ρ x length / area  

ρ = r x area / length  

ρ is in ohm-meters  

in basic units, it is m³kg/s³a²  

i think this is it.