A poll watcher
<span>a person who is paid by the parties to watch the voters and officials to make sure everything is fair</span>
Based on the information in the question, a light year is the distance traveled light in one year. Then if the light from the star Centauri takes 4.2 years to reach the earth, then its distance from earth is 4.2 light years.
<em>The correct answer is option</em><em> B.</em> The maximum height that can be reached by the stone is determined as 11.5 m.
<h3>
Maximum height attained by the stone </h3>
The maximum height attained by the stone when it is a 2/3 of its total height is calculated as follows;
v² = u² - 2gh
where;
- v is final velocity at maximum height, v = 0
- u is initial velocity
- g is acceleration due to gravity
0 = u² - 2gh
2gh = u²
h = u²/2g
h = (15²)/(2 x 9.8)
h = 11.48 m
h = 11.5 m
Thus, the maximum height that can be reached by the stone is determined as 11.5 m
Learn more about maximum height here: brainly.com/question/12446886
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Using the formula: E = kQ / d² where E is the electric field, Q is the test charge in coulomb, and d is the distance.
E = kQ / d²
k = 9 x 10^9 N-m²/C²
Q = 6.4 x 10^-5 C
d = 2.5 x 10^-2 m
Substituting the given values to the equation, we have:
E = (9 x 10^9)(6.4 x 10^-5) / (2.5 x 10^-2) ²
Electric field at the test charge is 921600000 N/C
