Rainy weekend: Sally is planning to go away for the weekend this coming Saturday and Sunday. At the place she will be going, the probability of rain on any given day is 0.10. Sally says that the probability that it rains on both days is 0.01. She reasons as follows:

P(Rain Saturday and Rain Sunday) = P(Rain Saturday) P( Rain Sunday) 

                                                              = (0.1)(0.1) 

                                                              = 0.01

a. What assumption is being made in this calculation?

b. Explain why this assumption is probably not justified in the present case.

c. Is the probability of 0.01 likely to be too high or too low? Explain.