In old style math, a span of a circle or circle is any of the line fragments from its middle to its edge, and in more current utilization, it is additionally their length.
In math, the circumference is the edge of a circle or oval.
A digression (tangent) to a circle is a straight line which contacts the circle at just one point.
A perpendicular bisector of a line section is a line fragment opposite to and going through the midpoint of (left figure).
Steps for constructions:
Given radius of 
1. Draw a circle of radius with center O using a ruler.
2. Now join the center S to the point P which is 
away from S.
3. Then, draw a perpendicular bisector of SP. Let us consider ‘O’ be the mid-point of SP.
4. Consider O as center and OS as radius; draw a circle cutting the first circle at Q and R.
5. Now join PQ and PR.
6. Therefore, PQ and PB are the required tangents. 7. Then the measure of PQ and PB are equal to
.
and 
, internal resistance 
and 
, connected in parallel. The equivalent emf of the combination is- (A) 
(B) 
(C) 
(D) 
and 
are collinear, prove that 
and 
be three points such that area of a 
is 4 sq units, find the value of 
.
and 
is 35 sq units.
and 
are collinear.
and 
are collinear.
and 
are collinear.
and 