The test results of 30 students for Chemistry, Physics and Biology are as follows. 18 pass Chemistry 17 pass Physics 21 pass Biology 12 pass both Chemistry and Physics 13 pass both Chemistry and Biology 1 1 pass both Physics and Biology 2 fail the three subjects (a) With the aid of a Venn diagram, find the number of students who pass the three subjects. Use C, P, and B as the events that a student passes Chemistry, Physics, and Biology, respectively. (b) Find the probability that a randomly selected student (i) passes the three subjects, (ii) passes only Chemistry, (iii) passes only Physics and Biology, (iv) fails Biology but passes Physics. (c) Write the event that a student passes only Chemistry using C, P, B, n, U, and complement whichever necessary. (d) Find P[(P'nB) UC]