Multiply: \text { iii) }\left(x^{5}+2 x^{4}-3 x^{3}+2 x^{2}+5 x+6\right) \text { by }\left(4 x^{3}+3 x^{2}+2 x+1\right) \text { ii) }\left(2 x^{2}+4 x+8\right) \text { by }\left(5 x^{3}+3 x^{2}-2 x-4\right) \text

{ i) }(x+1) \text { by }\left(2 x^{2}+3 x+2\right)