In a human pyramid in a circus, the entire weight of the balanced group is supported by the legs of a performer who is lying on his back (as shown in the figure below). The combined mass of all the persons performing the act, and the tables, plaques, etc. involved is $280~\text{kg}$. The mass of the performer lying on his back at the bottom of the pyramid is $60~\text{kg}$. Each thighbone (femur) of this performer has a length of $50~\text{cm}$ and an effective radius of $2.0~\text{cm}$. The amount by which each thighbone gets compressed under the extra load is: (The Young’s modulus for bone is given by, $Y = 9.4\times 10^9~\text{N/m}^{2}$)

A square lead slab of side $50~\text{cm}$ and thickness $10~\text{cm}$ is subject to a shearing force (on its narrow face) of $9.0\times 10^{4}~\text{N}.$ The lower edge is riveted to the floor as shown in the figure below. How much will the upper edge be displaced? (Shear modulus of lead $= 5.6\times 10^{9}~\text{Nm}^{-2}$)

The average depth of the Indian Ocean is about $3000~\text m.$ The fractional compression $\frac{\Delta V}{V},$ of water at the bottom of the ocean is? 
(Given that the bulk modulus of water is $2.2\times10^{9}~\text{Nm}^{-2}$ and $g=10~\text{ms}^{-2}$)
1. $1.36\times10^{-3}$
2. $2.36\times10^{-3}$
3. $1.36\times10^{-2}$
4. $2.36\times10^{-2}$