Water stored in a dam possesses

$A$ weightlifter lifts $240 \,kg$ from the ground to a height of $2.5 \,m$ in $3 \,s$. The average power is:

$A$ man drops a $10 \, kg$ rock from the top of a $20 \, m$ ladder. What will be its kinetic energy when it reaches the ground? What will be its speed just before it hits the ground? (Take $g = 10 \, m s^{-2}$)

An iron sphere of mass $10 \, kg$ has the same diameter as an aluminium sphere of mass $3.5 \, kg$. Both spheres are dropped simultaneously from a tower. When they are $10 \, m$ above the ground,they have the same

If an electric iron of $1200 \, W$ is used for $30$ minutes everyday, find the electric energy consumed in the month of April. (in $kWh$)

Compare the power at which each of the following is moving upwards against the force of gravity? (given $g = 10 \, m \, s^{-2}$)
$(i)$ $A$ butterfly of mass $1.0 \, g$ that flies upward at a rate of $0.5 \, m \, s^{-1}$.
$(ii)$ $A$ $250 \, g$ squirrel climbing up on a tree at a rate of $0.5 \, m \, s^{-1}$.