Final answer:
A partnership would be the recommended form of business ownership for Erick and Jacob.
Step-by-step explanation:
In this scenario, the most suitable form of business ownership for Erick and Jacob would be a partnership. A partnership is a business structure that allows two or more individuals to share ownership and responsibility for the business. Erick can continue his full-time position while still being involved in the accounting firm as a partner, sharing the profits and decision-making with Jacob.