1. A sampler has two strata with relative sizes W, = N;/N for 1 = 1, 2. He believes that S, and $2 can be taken as equal but thinks that c, must be between 2c, and 4c. He would prefer to use proportional allocation but does not wish to incur a substantial increase in variance compared with optimum allocation. For a given cost C = gin, + con2, ignoring the fpc, show that V ar prop WicI + Wacz Var opt (Wive + Wavez