I will attach my question.

; Exercise 12.12 Consider the structural equation and reduced form 1': = #311? +8; I; =TZ + u;- EEZieil=0 E[ziuil=0 with If treated as endogenous so that [E {1:38;} 7'5 0. For simplicity assume no intercepts. ya, zi, and I; are scalar. Assume 1r 3% 0. Consider the following estimator. First, estimate T by DLS of x,- on 2: and construct the tted values i}- = ?z,-. Second, estimate 33 by 01.5 of 1/; on if. [:1] Write out this estimator 3 explicitly as a function of the sample. [b] Find its probahity limit as n _. 00 [c] In general. is 3 consistent for ,8? Is there a reasonable condition under which ,3 is consistent