<em>Answer:</em>
B. a picture of Knife Edge Mirror Two Piece
<em>Step-by-step explanation:</em>
pls give brainliest, u don't have to
Did it on edge, hope u have a good day :)
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Answer:
thx for the points
Step-by-step explanation:
Find the rate in which both balls make one full rotation around the track.
Ball A:

It takes 30 seconds for Ball A to make a full rotation.
Ball B:

It takes 20 seconds for Ball B to make a full rotation.
Find the least common multiple of 20 and 30 to find the time at which they'll meet.
Multiples of 20: {20,40,60}
Multiples of 30: {30,60}
60 is the least common multiple of both 20 and 30.
The balls will meet again at
60 seconds.