Mark purchased a 270-day $500,000 bank bill (at a simple interest rate) on 15 July 2021. The purchase price was $490,550. He sold this bank bill on 13 August 2021.

(a) What was his selling price, if he sold this bank bill at a yield of 3.6% p.a. (simple interest)? Round your answer to three decimal places.

a. 488391.013 b. 488343.97 c. 488438.07 d. 487030.32

(b) Assume that Mark sold this bank bill at a simple interest rate of 3.6% p.a. up to the maturity date of the above bank bill. What is the annualised (simple interest) yield for this investment from 15 July 2021 to 13 August 2021? Round your answer to 3 decimal places in terms of percentage.

a. -5.862% b. -6.625% c. -5.238% d. -5.539%