A full journal bearing having clearance to radius ratio of $\frac{1}{100}$ using a lubricant with $\mu =28\times 10^{-3}$ Pa-s supports the shaft journal running at N=2400r.p.m. If bearing pressure is 1.4 MPa, the sommerfeld number is
(a) $8\times10 ^{-3}$ (b) $8\times10 ^{-5}$
(c) 0.48 (d) $0.48\times10 ^{-2}$