The scalar $$\overrightarrow A .\left( {\overrightarrow B + \overrightarrow C } \right) \times \left( {\overrightarrow A + \overrightarrow B + \overrightarrow C } \right)$$ equals :

A gas bubble, from an explosion under water, oscillates with a period T proportional to p^ad^bE^c. Where 'P' is the static pressure, 'd' is the density of water and 'E' is the total energy of the explosion. Find the value of a, b and c.

When a person walks on a rough surface, the frictional force exerted by the surface on the person is opposite to the direction of his motion.