2. In each part of this problem, the universe will consist of four numbers {1,2,3,4}. To complete the toy models, I'll be drawing lines connecting some of the numbers. C(x,y) means " x is connected to y." Consider the following toy models. (To make things simpler, these are just lines, not arrows, so C(x,y) and C(y,x) mean the same thing.) (a) Which of the above models satisfy the formula xyC(x,y) ? (b) Translate xyC(x,y) into an English sentence that doesn't use variables. (Hint: You might find it easier to use some equivalence laws to rewrite the formula before translating.) (c) Which of the above models satisfy the formula xyC(x,y) ? (d) Translate xyC(x,y) into an English sentence that doesn't use variables. (e) Which of the above models satisfy the formula xyC(x,y) ? (f) Translate xyC(x,y) into an English sentence that doesn't use variables