1. For each of the following sets of three planes, determine (by inspection) which diagram describes the intersection of the planes. Give a brief explanation for your selection. [10 marks - 2 marks each] [ m: x+2y+3:-4=0 a) a. #2: 3x+ 6y+9z-12 =0 *3: 5x + 10y+15: -20 = 0 b) b. m: x+2y+3:-4=0 72: 3x +6y+92-11=0 #3: 5x +10y+15=-16 =0 C. *1: x+2y+3:-4=0 #2: 3x + 6y+9z -12 =0 my: 5x +10y+15: -16=0 d) d. m: x+2y+3:-4=0 #2: 3x+6y+9z -12 = 0 my: 3x +5y-2z-1=0 #1: x+2y+3z-4=0 e. 72: 3x + 6y+92-11=0 f) m3: 3.x+ 5y-2:-1=0