66mm
Step-by-step explanation:
The circumference of a circle is given by
C =2 pi r
22/7 * 2( 10.5)
22/7 * 21
66
coin flip
non-answer:
choosing
sorry if this isnt what you're looking for i dont really understand the question
answer: translate the circles so they share a common center point and dilate circle y by a scale factor of 3.