Refer to case law and/or statutory authority where appropriate and relevant to support your answers. Use IRAC method.

Chris, Mia, and Lily teamed up to establish a health consultancy named "WellVibe." Chris and Mia secured a cozy office space, elevating its atmosphere with a healthfocused fitout and interior design. Lily meticulously curated the office environment by selecting state-of-the-art fitness equipment and wellness tools, including exercise machines, nutritional supplements, and health monitoring devices. Their collective efforts extended to recruiting a team to manage daily health operations.

After a successful six months, Chris decided to step back from the health business to focus on family commitments. Both Mia and Lily agreed to carry on running the consultancy under the same name. Heather, who has been providing essential health components such as organic supplements and specialized exercise equipment to the business since its inception, continues to do so without being aware that Chris is no longer one of the business owners. Chris's departure resulted in a reduction in the revenue of the business. Heather has not been paid for four months of supplies and is considering pursuing legal action against Chris, Mia, and Lily to recover the owed payments.

Meanwhile, tensions escalated between two wellness consultants on the business premises, sparking disputes over the organization of health workshops and about who oversees the implementation of personalized health plans for clients.

On a particular day, a client named Sarah ordered a customised wellness solution for her fitness centre. Amidst an office disagreement, an unfortunate oversight occurred: a crucial health feature was omitted from the solution due to a miscommunication. As a result, Sarah's business encountered issues after implementing the solution.

(a) Explain the type of business structure Chris, Mia, and Lily have formed and advise Heather who she can sue for the debt. (3 Marks)

(b) Advise Sarah if the owners of WellVibe and/or the wellness consultants be liable for the loss suffered by her. (3 Marks)