Alice, William, and David jointly own and operate a supermarket business known as Grocer's Haven. All three partners actively participate in the business, which encompasses a total of five stores at different locations.

Laura is an employee of the firm, responsible for working at the checkout counter in the Nadi store.

Jessica is an individual entrepreneur who owns and operates a spice business. Her business involves packaging spices for sale to consumers, mainly food retailers. Jessica has been a supplier to Grocer's Haven for many years.

In addition to her business ventures, Jessica, like any regular shopper, frequently shops for groceries at the Grocer's Haven store in Nadi.

On Friday, William contacts Jessica and places an order for spices. They agree on the types and quantities of spices, the price, payment terms (7 days), and delivery date, constituting a contract.

On Saturday, Jessica, as usual, does her weekly shopping at the Nadi Grocer's Haven store, purchasing a bag of rice. She uses the checkout counter staffed by Laura.

The events in the story involve contractual agreements between Jessica and Grocer's Haven, leading to the following questions:

(i) How does Jessica have a binding contract with Grocer's Haven for the supply of spices when dealing with William? Reference relevant legal rules.

(ii) How does Jessica have a binding contract with Grocer's Haven for the purchase and sale of a bag of rice when dealing with Laura? Reference relevant legal rules.

(iii) If Jessica delivers the spices ordered by William but doesn't receive payment, who can she sue for breach of contract? Explain with reference to relevant legal rules.

(iv) If the rice purchased by Jessica is contaminated and she returns it but the store manager refuses a refund, who can Jessica sue for breach of contract? Explain with reference to relevant legal rules.