A portfolio consists of three stocks. The weight, expected rate of return and systematic risk for each stock are provided in the following table.

Stock Investments Expected return
A $7,500 20%
B $10,000 15%
C $2,500 10%

Beta
1.5
1
0.9

a) Calculate the weights invested in stocks A, B and C, respectively.

b) Calculate expected return on the portfolio.

c) Calculate the systematic risk of the portfolio, i,e. the portfolio beta