Answer: Option a, concave lens.
Explanation: The object that collects the light in a reflecting telescope is "kinda" concave lens that collects the light and directs it to a mirror, that is where the observer can see. So the correct answer is option a.
Answer:
21.53 x 10^{6} N
Explanation:
force (F) = 4.71 x 10^{3} N
distance (s) = 4.57 km = 4570 m
how much work is done.
work = force x distance
work = 4.71 x 10^{3} x 4570 = 21.53 x 10^{6} N
Hi
the dancers wish to increase their grip which takes advantage of the force of friction.
B
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