Julie has been appointed Company Secretary of Green Pty Ltd$.$ She is authorised by the company$$s constitution to sign contracts of an administrative nature of up to $$5,000$ and expenditure in excess of $$5,000$ requires members$$ approval. Julie signs a contract to buy $100$ boxes of plain $($recycled$)$ printing paper from Paper Inc. for $$8,000$ without seeking members$$ approval. Which of the following statements is correct?

a$.$

Green Pty Ltd is not bound by the contract because Julie has no authority to enter into a $$8,000$ contract with Paper Inc.

b$.$

Green Pty Ltd is bound by the contract since Company Secretaries can always bind the company in contract.

c$.$

Green Pty Ltd is not bound by the contract even though Julie as Company Secretary has customary power to enter into such contracts since Paper Inc would have known that Julie does not have authority from the company$$s constitution.

d$.$

Green Pty Ltd is bound by the contract since Julie as Company Secretary has customary power to enter into such contracts and Paper Inc would not have known that Julie does not have authority.