A circle has points P, Q, R on a circle in such a way that angle PQR is 60 deg and angle QRP is 80 deg. Calculate the angle subtended by an arc QR at the centre.
Two particles with charges q1 and q2 are kept at a certain distance to exert force F on each other. If the distance is reduced to one-fifth, then the force between them is
A sentence has been given in Direct/Indirect Speech. Out of the four given alternatives, select the one which best expresses the same sentence in Indirect/Direct Speech.