I put my solutions to 16 here http://community.boredofstudies.org/showthread.php?t=293623
ai) simple expansion of the difference of two roots being greater than zero
aii) (x-1)>=0 , y-x>=0 multiply and your done
aiii) the left inequality is part ii, the right is part i.
iv) didn't attempt
bi) conjugate root theorem, mention that the conjugate of ia is -i*the conjugate of a.
ii) split the third term of the polynomial into two parts and factorise the two parts
iii) didn't do
iv) product of the roots, then say something about how conjugate alpha times alpha is the modulus of alpha
v) sum of roots