an investor has a portfolio with 30% invested in gold stocks, and 70% in industrial stocks. \it is expexted that gold stocks will provide 4% return ina good economy and 18% in a poor economy. Industrial stocks are expexted to provide 9% return in a good economy and -9% ina poor economy. The probability of a good economy is $40% and 60% in a poor economy. given this info calculate the expected rate of return on the portfolio.