X = \(\frac{4}{3}\) r = ?
 Shell’s law:. 7 = \(\frac{Sin 2^0}{ Sin r^0}\)
 \(\frac{V}{g}\) = \(\frac{Sin 30^0}{Sin r^0}\)
 Sin\(r^0\) = \(\frac{3 Sin 30^0}{4}\)
 Sin \(r^0\) = 0.375
 R \(^o\) = Sin-1 (0.375)
 R \(^o\) = 22.02 \(^o\)
 R \(^o\) = 22 \(^o\)