Formula used to find the circumference of a circle is

(a)

2πr units

(b)

πr² + 2r units

(c)

πr² sq. units

(d)

πr³ cu. units

In the formula, C = 2πr, ‘r’ refers to

(a)

circumference

(b)

area

(c)

rotation

(d)

radius

If the circumference of a circle is 82π , then the value of ‘r’ is

(a)

41 cm

(b)

82 cm

(c)

21 cm

(d)

20 cm

Circumference of a circle is always

(a)

three times of its diameter

(b)

more than three times of its diameter

(c)

less than three times of its diameter

(d)

three times of its radius

The formula used to find the area of the circle is ________ sq.units.

(a)

4πr²

(b)

πr²

(c)

2πr²

(d)

πr² + 2r