What is the bulk modulus of a perfectly rigid body?

$A$ sphere contracts in volume by $0.01 \%$ when taken to the bottom of a sea $1 \,km$ deep. Find the Bulk modulus of the material of the sphere in $N/m^2$.

The compressibility of water is $5 \times 10^{-10} \ m^2/N$. $A$ pressure of $15 \times 10^6 \ Pa$ is applied on $100 \ ml$ volume of water. The change in the volume of water is:

Compute the bulk modulus of water from the following data: Initial volume $= 100.0 \; L$,Pressure increase $= 100.0 \; atm$ $(1 \; atm = 1.013 \times 10^{5} \; Pa)$,Final volume $= 100.5 \; L$. Compare the bulk modulus of water with that of air (at constant temperature). Explain in simple terms why the ratio is so large.

Bulk modulus of water is $2 \times 10^9 \ N/m^2$. The pressure required to increase the volume of water by $0.1 \%$ in $N/m^2$ is:

The compressibility of water is $6 \times 10^{-10} \,m^{2}/N$. If one litre of water is subjected to a pressure of $4 \times 10^{7} \,N/m^{2}$, then the decrease in its volume in millilitre will be