Can you say that salt is a liquid on the basis of change in its shape? Justify your answer. Take a sponge. Observe its shape.

Can you find the HCF of 1.2 and 0.12? Justify your answer.

Let us stretch a rubber band. Is there a change in its shape?

If f (c ) does not exist , can f(x) have an extremum at x=c ? Justify your answer taking f(x)=|x|andc=0 .

In PCl_(5) phosphorus is in sp^(3) hybridised state but all its five bonds are not equivalent. Justify your answer with reason.

Determine the change in potential energy of a body when it is raised through a height h, inside water. Volume of the body is V, its density is rho and the density of water is rho_(0) . Given your answer for the situations when (i) rhogtrho_(0) and (ii) rholtrho_(0) .

Cut a right angled triangle, stick a string along its perpendicular side, as shown in fig. (i) hold the both the sides of a string with your hands and rotate it with constant speed. What fo you observe?