State whether the following are true or false in relation to the auditor and fraud

1. It is the auditor’s responsibility to follow up possible indicators of fraud uncovered during the course of their audit testing work even if they are not material
2. External auditors must approach their audit testing with an attitude of professional scepticism
3. Management can rely on auditors to detect fraud as this is one of the auditor’s duties under ISA 240 ‘The auditor’s responsibilities relating to fraud in an audit of financial statements’ 
4. Auditor’s must consider the effect any fraud which has been uncovered might have on their audit opinion