Lynn and Jack jointly own shares of stock of a corporation, have a joint bank account, and have purchased and own as tenants in common a piece of real estate.

They share equally the dividends paid on the stock, the interest on the bank account, and the rent from the real estate.

Without Lynn's knowledge, Jack makes a trip to inspect the real estate and on his way runs over Samuel.

Samuel sues Lynn and Jack for his personal injuries, joining Lynn as defendant on the theory that Lynn was Jack's partner. Is Lynn a partner of Jack?