To warn ships for underwater rocks, a lighthouse spreads a red coloured light over a sector of angle `80^(@)` to a distance of 16.5 km. Find the area of the sea over which the ships are warned. `(" Use "pi=3.14).`

A chord of a circle of radius 10 cm subtends a right angle at the centre. Find the area of the corresponding : major sector. (" Use "pi=3.14).

As observed from the top of a 100 m high light house from the sea level the angle of depression of two ships are 30^(@) and 45^(@) . If one of the ship is exactly behind the other on the same side of the light house, find the distance between the two ships. (sqrt(3)=1.73) .

As observed from the top of a 100 m high light house from the sea level the angle of depression of two ships are 30^(@) and 45^(@) . If one of the ship is exactly behind the other on the same side of the light house, find the distance between the two ships (sqrt(3) ~~1.73) .