<em>The correct option is </em><em>A</em>. The information we know about the known exoplanets is estimates of orbits and masses.
<h3>What is exoplanets?</h3>
An exoplanet or extrasolar planet is a planet outside the Solar System.
In other words, exoplanet is any planet beyond our solar system.
<h3>Characteristics of exoplanets</h3>
exoplanets are known for the following characteristics;
- they are usually hot
- they can orbit their stars so tightly that a “year” lasts only a few days
- they can orbit two suns at once
Thus, the information we know about the known exoplanets is estimates of orbits and masses.
Learn more about exoplanets here: brainly.com/question/1514493
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Path length is 2*pi*0.4=2.512
Speed=distance/time
Speed =2.512/0.2=12.56m/s
Speed is the rate at which something covers a distance; velocity is the same but it takes into account whether it goes forwards or backwards; and acceleration is the rate of an increase in speed.
Answer:
B-Large groups of stars held together by gravity
Explanation:
Answer:
the angular velocity of the car is 12.568 rad/s.
Explanation:
Given;
radius of the circular track, r = 0.3 m
number of revolutions per second made by the car, ω = 2 rev/s
The angular velocity of the car in radian per second is calculated as;
From the given data, we convert the angular velocity in revolution per second to radian per second.

Therefore, the angular velocity of the car is 12.568 rad/s.