Find the area of the trapezium ABCD in which AB//DC, AB = 18 cm, ∠B = ∠C = 90°, CD = 12 cm and AD = 10 cm.

The circumference of a circle is numerically same as its area; then its radius is :

1. 4 unit

2. 2 unit

3. 1 unit

4. none of these

The circumference of a circle is equal to the sum of the circumferences of two circles with radii 10 cm and 12 cm. The radius of the circle formed is :

1. 2 cm

2. 44 cm

3. 22 cm

4. 244 cm

The diameter of a circular wheel is 56 cm. The distance moved by it in 100 rounds is :

1. 176 cm

2. 17600 cm

3. 1760 cm

4. 352 cm