Seven tables are arranged in a line with Chairs on either side as shown in the figure (tables:blue; chairszmagenta). Seven people come along and sit at the seven tablesThey sit independently and randomly on one side of the table or the other. Let X denote the number of people that have no one directly looking at them. I(For example if the people sit as shown in the figure (red dots : people), the first person, fourth person and fifth person have no one looking at them, while person 1 looks at person 2; persons 2 and 4 look at person 3; persons 5 and 7 look at person 6; and person 6 looks at person 7). Find E(X). (it may be helpful to express X as a sum). A chemistry lab assignment has 3 delicate experiments. Each takes 10 minutes to perform. When you arrive at the lab, you are assigned to do one of the experiments with equal probability. You have to repeat your assigned experiment until you get a successful outcome. The first experiment has a 10% success rate; the second has a 16% success rate and the third has a 18% success rate. If X is the number of minutes before you can leave, what is the expected value of X