Question : A is the centre of a circle whose radius is 8 units, and B is the centre of a circle whose diameter is 8 units. If these two circles touch externally, then the area of the circle with diameter AB is:

Option 1: $36\pi$ sq. units

Option 2: $64\pi$ sq. units

Option 3: $144\pi$ sq. units

Option 4: $256\pi$ sq. units

Question : Two circles touch each other externally. The radius of the first circle with centre O is 12 cm. Radius of the second circle with centre A is 8 cm. Find the length of their common tangent BC.

Option 1: $6\sqrt{6}\mathrm{cm}$

Option 2: $8\sqrt{3}\mathrm{cm}$

Option 3: $8\sqrt{2}\mathrm{cm}$

Option 4: $8\sqrt{6}\mathrm{cm}$

Question : The area of triangle with vertices A(0, 8), O(0, 0), and B(5, 0) is:

Option 1: 8 sq. units

Option 2: 13 sq. units

Option 3: 20 sq. units

Option 4: 40 sq. units

Question : Two circles touch each other externally. The radius of the first circle with centre O is 6 cm. The radius of the second circle with centre P is 3 cm. Find the length of their common tangent AB.

Option 1: $3\sqrt{2}$ cm

Option 2: $4\sqrt{2}$ cm

Option 3: $6\sqrt{3}$ cm

Option 4: $6\sqrt{2}$ cm

Question : There are two circles which touch each other externally. The radius of the first circle with centre O is 17 cm and the radius of the second circle with centre A is 7 cm. BC is a direct common tangent to these two circles, where B and C are points on the circles with centres O and A, respectively. The length of BC is:

Option 1: $2\sqrt{118}$ cm

Option 2: $2\sqrt{119}$ cm

Option 3: $2\sqrt{113}$ cm

Option 4: $2\sqrt{117}$ cm

Question : ABCD is a square inscribed in a circle of radius $r$. Then the total area (in square units) of the portions of the circle lying outside the square is:

Option 1: $\pi (r^2-4)$

Option 2: $2\pi (r^2-1)$

Option 3: ${\pi }^{2}r(r-7)$

Option 4: $r^2(\pi -2)$