I have problem in solving the following linear algebra

Suppose y : X+e,X is n by p, n > p. Denition: AT is estimable if ATB : pTX for some pT. In words, linear combinations of means of y are dened to be estimable. To match the book's notation, AT and pT are individual rows of AT and PT respectively. 1. Suppose X has full rank and you are given a vector AT. Construct a pT so that pTX = AT. 2. Now suppose that X doesn't have full rank. For instance, suppose E(y) : 1 1 0 0 1 1 0 0 g 1 0 1 0 l . Find 4 (different) non-identiable linear functions of ,8 and 4 1 0 1 0 52 1 0 0 1 [33 1 0 0 1 (different) identiable functions. (Show that they are not identiable and identiable too.)