An experiment succeeds twice as often as it fails. The probability of at least 5 successes in the six trials of this experiment is :

The angle of elevation of the top of a vertical tower from a point A, due east of it is 45^o. The angle of elevation of the top of the same tower from a point B, due south of A is 30^o. If the distance between A and B is $$54\sqrt 2 \,m,$$ then the height of the tower (in metres), is :

The contrapositive of the following statement,

“If the side of a square doubles, then its area increases four times”, is :

A particle of mass M is moving in a circle of fixed radius R in such a way that its centripetal acceleration at time t is given by n² R t² where n is a constant. The power delivered to the particle by the force acting on it, is :