What are the 2 required ways of controlling leakage in plastics and define intensity of pressure with calculation?

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3c) What are the 2 required ways of controlling leakage in plastics?
Two ways to control leakage in plastic storage systems are:

1. Repair: For minor cracks or holes, specialized plastic welding, sealants, or adhesive patches can be used to seal the leak.
2. Replacement: If the damage is extensive, structural, or cannot be effectively repaired, the damaged section or the entire plastic storage system should be replaced.

5a) Define intensity of pressure.
The intensity of pressure is another term for pressure, defined as the force exerted perpendicularly per unit area on a surface. In fluids, it represents the force per unit area exerted by the fluid.

5b) If a storage cistern was (400 x 300 x 200) mm, Calculate the intensity of pressure in such vessel.
Given dimensions of the cistern: $400 \text{ mm} \times 300 \text{ mm} \times 200 \text{ mm}$.
We assume the cistern is filled with water to its maximum height. The height of the water column ($h$) will be the smallest dimension, $200 \text{ mm}$, as this is typically the vertical dimension for a cistern.
Density of water ($\rho$) = $1000 \text{ kg/m}^3$
Acceleration due to gravity ($g$) = $9.81 \text{ m/s}^2$