A portfolio is composed of two stocks, A and B. Stock A has a standard deviation of return of 21%, while stock B has a standard deviation of return of 27%. Stock A comprises 70% of the portfolio, while stock B comprises 30% of the portfolio. If the variance of return on the portfolio is .045, the correlation coefficient between the returns on A and B is _________.

	.707
	.191
	.212
	.495 *EXPLAIN HOW TO DO PROBLEM*