14. Let 2 1" " , Z, be independently distributed as N(r;, a;), i = 1, .. . , s, where the 0 ; are known constants. (i) With respect to a suitable group of linear transformations there exists a UMP invariant test of H: t1 = .. . = ts given by the rejection region (21). (ii) The power of this test is the integral from C to 00 of the noncentral x 2-density with s - 1 degrees of freedom and noncentrality parameter )..2 obtained by substituting t for Z; in the left-hand side of (21).