Three identical 180-day $100,000 bank bills have been respectively sold to three investors at a price of $97,500 on 15/1/2017. The After the purchase, these three investors have sold their bills at different yield rate on different dates to realise their capital gain/loss. Please see table 1 for their investment details. (30 marks) Table 1: Investment details. Investor's Name Adam Bill Selling date Capital gain/loss 28/2/2017 14/3/2017 15/2/2017 $60 $170 a. [8 marks] Calculate the purchase yield rate (simple interest rate).