If the difference between circumference and diameter of a circle is 30 cm, then the radius of the circle must be?.

A) \$6 cm\$

B) \$7 cm\$

C) \$75 cm\$

D) \$8 cm\$

The ratio of the outer and the inner perimeter of a circular path is 23:22. If the path is 5 meters wide, the diameter of the inner circle is

A) \$110 m\$

B) \$55 m\$

C) \$220 m\$

D) \$230 m\$

Four equal circles each of radius 'a' units touch one another. The area enclosed between them in square units is.

A) \$3a^2\$

B) \$(6a^2)/7\$

C) \$(4a^2)/7\$

D) \$(a^2)/7\$

A circular wire of radius 42 cm is bent in the form of a rectangle whose sides are in the ratio of 6:5. The smaller side of the rectangle is.

A) \$60 cm\$

B) \$30 cm\$

C) \$25 cm\$

D) \$36 cm\$

The area of the greatest circle, which can be inscribed in a square whose perimeter is 120 cm, is.

A) \$\frac{22}{7} \times (15)^2 cm^2\$

B) \$\frac{22}{7} \times (7/2)^2 cm^2\$

C) \$\frac{22}{7} \times ((15)/2)^2 cm^2\$

D) \$\frac{22}{7} \times ((9)/2)^2 cm^2\$