We can apply the formula for Hydraulic diameter De = \(\frac{4×(D_{io}^2 – D_{oi}^2)×\frac{π}{4}}{π(D_{io}+D_{oi})}\) only when _________(i) We are calculating Reynolds number for the annulus tube(ii) We are calculating Reynolds number for the inner tube(iii) We are calculating heat transfer coefficient for the annulus tube

We can apply the formula for Hydraulic diameter De = \(\frac{4×(D_{i

1.	We can apply the formula for Hydraulic diameter De = \(\frac{4×(D_{io}^2 – D_{oi}^2)×\frac{π}{4}}{π(D_{io}+D_{oi})}\) only when _________(i) We are calculating Reynolds number for the annulus tube(ii) We are calculating Reynolds number for the inner tube(iii) We are calculating heat transfer coefficient for the annulus tube
A.	(ii)(iii)
B.	(i)
C.	(i)(ii)
D.	(i)(ii)(iii)
Answer» C. (i)(ii)