You are planning the audit of Bluechip Ltd, a company with investments in listed securities that you consider to have a low level of inherent risk. What is the most appropriate level of planning materiality for the 30 June 2022 audit given the following balances: (all amounts are in $'000) Sales: 1280 (2022); 1152 (2021); 1024 (2020) Profit: 24.5 (2022); 200.9 (2021): -171.5 (2020) Current assets: 1950 (2022); 1755 (2021); 1560 (2020)

a. 1.2

b. 12.8

c. 2.5

d. 19.5