casual vacancy due to death of auditor

cmacs sathya (31 Points)

23 March 2019  
the private company appointed ABC& co an Auditor firm with two partners. one of the partner died and the firm got dissolved, the remaining partner become proprietor in same firm name. please suggest
1. whether it is casual vacancy due to death of one of partner or due
to resignation
2. whether ADT 1 can be filed directly by appointing new auditor
3. whether remaining partner has to file adt3 as resignation and want to appoint new auditor