5. 6.23 A total of $50,000 was invested in projects to reduce insider theft in an appliance warehouse. The two projects, identified as Y and Z, were implemented for 1 year each. Based on the significantly reduced losses, the overall rate of return on the $50,000 was determined to be 40%, with the ROR on the $20,000 invested in Y at 15%.

(a) What was the size of the investment in Z, and

(b) what was the rate of return on Z?