In geometry it would indicate a radius. More generally, it would indicate a Registered Trademark.
R = Radius The radius is half the diameter of a circle.
You mean what Is the circumference of a circle? pi*(r)squared.
radius
A little R in a circle usually means "registered trademark".
It is r*sqrt(2) = 1.414*r, approx.
A circle does not have a circumstance. Assuming that you mean circumfernece, the answer is c = 2*pi*r
It is the symbol for Alcoholics Anonymous.
stronger?
a cirlce with a v inside it means that its a volt meter
The area of a circle is the number of square units inside that circle, if each square in the circle to the left has an area of 1cm2, you could count the total number of squares to get the area of this circle. However, it is easier to use one the following formulas; A=.r²or A=pi times r times r, where A is the area and r is the radius.
A c inside a circle means "with" in medical terms.
You are describing a railroad crossing sign.