4. A consultant has been working for the manager of an investment fund for ten years. At the beginning of their working relationship, the consultant sent the investment manager a contract for the first year of work, detailing how much compensation he expected and other terms, which the manager never signed or returned. However, shortly after receiving the contract, the manager sent the consultant some work, and the consultant completed it. The consultant continued to complete a few projects a year for the manager, though he never sent him another contract. The consultant kept track of his time and sent the manager a bill once a year at the end of the year, which the manager always promptly paid. This year, however, the manager is refusing to pay the bill on the grounds that he did not have a contract to pay the consultant for his services. If the consultant sues the investment manager for the amount of the unpaid bill, will he be successful?