Answer:
The inner diameter of the steam tube is 0.1185 m.
Step-by-step explanation:

m = mass flow rate
= density of the liquid
V=specific volume =

v = velocity of the liquid
A = area of cross-section
Diameter of the cross-section = d = 2r
Given: m = 18 kg/s, v = 60 m/s,A=?,



Area of the inner cross section =


d = 0.1185 m
The inner diameter of the steam tube is 0.1185 m.