A stock broker received an order from a client to buy 11,000 shares of CBA within ten minutes. Within those ten minutes, the following trades took place. The broker's clients are marked with a "*".

Time	Price	Quantity
12:02:05	87.43	1300
12:04:57	86.74	1800
12:05:22	85.96	4200*
12:07:30	86.04	4900
12:08:12	85.78	3400*
12:08:57	85.71	9700
12:09:35	84.78	3400*

a) Calculate the market volume-weighted average price.

b) Calculate the stock broker's volume-weighted average price. (2 marks)

c) Using the volume-weighted average price method, assess the broker's execution performance.

d) Discuss the advantages and disadvantages of using the volume-weighted average price as tool for evaluating trading performance.