Answer:
Option B
Explanation:
With end correction
$f=n\left[\frac{v}{4(1+e)}\right],$ where n=1,2,3....
$=n\left[\frac{v}{4(1+0.6r)}\right]$
because e=0.6 r , where r is radius of pipe
for first sentence ,n=1
$\therefore$ $f=\frac{v}{4(l+0.6r)}$
or $l=\frac{v}{4f}-0.6r$
= $\left[\left(\frac{336 \times100}{4 \times 512}\right)-0.6\times2\right]cm$
=15.2 cm