please provide excel formulas

1-

If P(A) = 0.3, P(B) = 0.4, and P(A and B) = 0.2, are A and B independent?

2-

How will marketers change their organic (unpaid) social media postings in the near future? A survey by Social Media Examiner reported that 65% of B2B marketers (marketers who focus primarily on attracting businesses) plan to increase LinkedIn organic social media postings, as compared to 43% of B2C marketers (marketers who primarily target consumers). The survey was based on 1,947 B2B marketers and 3,779 B2C marketers. The following table summarizes the results.

a. Suppose you know that the marketer is a B2B marketer. What is the probability that he or she plans to increase LinkedIn or-ganic social media postings?

b. Suppose you know that the marketer is a B2C marketer. What is the probability that he or she plans to increase LinkedIn organic social media postings?

c. Are the two events, increase LinkedIn postings and business fo-cus, independent? Explain.

	business focus
increase linkedin postings?	b2b	b2c	total
yes	1266	1625	2891
no	681	2145	2835
total	1947	3779	5726