Suppose an electrically charged ruler transfers some of its
charge by contact to a tiny plastic sphere. will the ruler and the sphere
attract or repel afterwards? why?

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.

for step 7 table c on the lab "newtons law of action"   the average time it took the car to travel .25 meters   was 1.92 seconds.

the average time it took the car to travel 0.50 meters was 2.61 seconds

hope this : )