The angles of depression of two ships from the top of a light house are 45° and 30° toward east. If the ships are 200m apart, the height of the light house is (take √3=1.73)
In a certain code, 'book is big' is written as 756; 'big is story' is 764 and 'story book is interesting' is 4356. Which digit represents 'interesting'?