from the BHP annual report. kindly answer in details the following.

1) The revenue, Earnings before Interest and Tax and Net Operating Cash Flow have all improved from 2020 to 2021. An investor has asked you to explain the reason for the improvement and the sustainability of the improvement. Based on the annual report explain to the investor the reasons for the improved financial performance and its sustainability.

2) Critically evaluate BH's stakeholder engagement in the contexts of the Brazilian Dam tragedy.

3) Discuss the role of audit committee of BHP and do you feel it has carried out its role effectively. You need to provide evidence to support your answer.