**3.8** *Test of the "right-angle" distance metric,
revisited* In Example 4 we obtained the probability law for the random variable R, the
ratio of the right-angle and Euclidean distances. In particular, we found
**E[R] = 4/ 1.273 **
^{2}_{R}
= 1 + 2/ - 16/^{2}
Derive these results directly *without* first obtaining F_{R} or f_{R} |