State Pascal's law.

$A$ hydraulic press can lift $100\, kg$ when a mass $'m'$ is placed on the smaller piston. It can lift ......... $kg$ when the diameter of the larger piston is increased by $4$ times and that of the smaller piston is decreased by $4$ times,keeping the same mass $'m'$ on the smaller piston.

Two syringes of different cross-sections (without needles) filled with water are connected with a tightly fitted rubber tube filled with water. Diameters of the smaller piston and larger piston are $1.0 \; cm$ and $3.0 \; cm$ respectively.
$(a)$ Find the force exerted on the larger piston when a force of $10 \; N$ is applied to the smaller piston.
$(b)$ If the smaller piston is pushed in through $6.0 \; cm$,how much does the larger piston move out?

Name two devices working on Pascal's law.

$A$ hydraulic automobile lift is designed to lift cars with a maximum mass of $3000 \, kg$. The area of cross-section of the piston carrying the load is $425 \, cm^{2}$. What is the maximum pressure the smaller piston would have to bear?

$A$ hydraulic lift is shown in the figure. The radii of the movable pistons $P_1$ and $P_2$ are $2 \ m$ and $5 \ m$ respectively. If a block of mass $x$ is placed on $P_2$,then the minimum mass that should be kept on $P_1$ to lift the block on $P_2$ is (in $x$)