(a) In the complete expansion of (a + b + c + d) ∙ (e + f + g + h)(u + v + w + x + y + z) one obtains the sum of terms such as agw, cfx, and dgv. How many such terms appear in this complete expansion?
(b) Which of the following terms do not appear in the complete expansion from part (a)?
(i) afx
(ii) bvx
(iii) chz
(iv) cgw
(v) egu
(vi) dfz