20km every 1 hr is what 20km/hr means.
so 3hrs is 20km*3=60km.
Answer:
q=1.4*10^{-9}C
Explanation:
Given data:
charge on ruler = -14μC
Mass of tissue is 5 g
To Know the minimum charge, equate electrostatic force to weight
we have F = W
so
putting all value in equation,

solving for q

or q=1.4*10^{-9}C
<span>When reading a buret, the initial reading should be taken from the top of the glassware and the final volume should still taken at the top. If the buret is completely, the initial volume for most buret would be zero. though, there are some where their initial starts at 50 decreasing to zero.</span>
A. attract each other.
The Law of Universal Gravitation discusses the phenomenon of gravity. Remember that gravity is the force that keeps us on Earth; the Earth pulls us down, and our bodies pull back. Gravity is the force of attraction, so the correct answer is a).