The angle of elevation of the top of a tower from a point A on the ground is 30^o. On moving a distance of 20 m towards the foot of the tower to a point B, the angle of elevation increase to 60^o.The height of the tower is-

In a triangle, if three altitudes are equal, then the triangle is 

If ABC is an equilateral triangle and D is a point on BC such that AD⊥BC, then 

If the circumradius of an equilateral triangle be 10 cm, then the measure of its in-radius is

The perimeter of five squares are 24 cm, 32 cm, 40 cm, 76 cm and 80 cm respectively. The perimeter of another square equal in area to sum of the areas of these squares is: 

From four corners of a square sheet of side 4 cm, four pieces, each in the shape of arc of a circle with radius 2 cm, are cut out. The area of the remaining portion is:

Direction: From the given alternatives select the word which cannot be formed using the letters of the given words.
"COMPETITION" 

If Friday falls on 15th of September 2000, what will be the day of 15th of September 2001?