F.4CA Winnie Leung (22)
HARDER PROBLEMS: 

   6) Since in line 4, 5 --- P=-5, Q=3 
   therefore in line 6 --- P= -5 * 3 =-15 
   and in line 7 --- Q=-15/3 = -5 
   and in line 8 --- P=-15/-5 = 3. 

   Therefore the value of P is 3. 

   7) The answer is (E). 
   ~~~ if (not(5=3*2+1)) or (4<3) then A:= A+3 ~~~ 
   For the first half of this conditional 
   statement, i.e. (not(5=3*2+1)), 
   R.H.S.= 5 
   L.H.S.=3*2+1= 7 
   Hence (not(5=3*2+1)) is true. 
   Since the conditional statement is an "or" 
   statement, then when either one condition is 
   true, the whole condition will be true. 
   As a result, it does not need to prove (4<3). 
   And the prefect answer is (E). 

   8) The answer is C. 
   When X>=0, the computer will read: 
   X is positive 
   Y = 1 
   Z = X * Y 
   Hence the value of Z must be equal to X. 
   When X<0, the computer will read: 
   X is negative 
   Y = -1 
   Z = X * Y 
   Hence the value of Z must be equal to absolute value of X. 
   As a result, the value of Z will be equal to the absolute value of X .