For the same draw down in two observations wells at distances r1 and r2, the times after start of
pumping are t1 and t2 hours respectively. The relation which holds good is
(A) t2 = r2/r1 × t1
(B) t2 = (r2/r1)² × t1
(C) t2 = (r2/r1)3
× t1
(D) t2 = (r2/r1) × t1
2