With respect to fluid flow, match the following in Column X with Column Y:

Which one of the following combinations is correct?
Step 1: Analyze Viscosity (P)
Viscosity is related to the Reynolds number (II), which is a measure of the relative importance of inertial forces to viscous forces in fluid flow.
Step 2: Analyze Gravity (Q)
Gravity influences the Froude number (IV), which is a measure of the relative importance of inertial forces to gravitational forces in open channel flows.
Step 3: Analyze Compressibility (R)
Compressibility is related to the Mach number (I), which measures the ratio of flow velocity to the speed of sound in the fluid.
Step 4: Analyze Pressure (S)
Pressure is related to the Euler number (III), which is a dimensionless number used to describe the balance between pressure forces and inertial forces.
Final Answer: (A) (P) – (II), (Q) – (IV), (R) – (I), (S) – (III)
A venturimeter as shown in the figure (not to scale) is connected to measure the flow of water in a vertical pipe of 20 cm diameter. 
Consider a five-digit number PQRST that has distinct digits P, Q, R, S, and T, and satisfies the following conditions:
1. \( P<Q \)
2. \( S>P>T \)
3. \( R<T \)
If integers 1 through 5 are used to construct such a number, the value of P is:



