Bill Dukes has $100,000 invested in a 2 stock portfolio; $75,000 is invested in Stock X and the remainder is invested in Stock Y. X's beta is 1.50 and Y's beta is 0.70. What is the portfolio's beta?
A. 1.30
B. 1.00
C. 0.98
D. 1.39
E. 1.44