6.1 Joe has a written agreement with Naomi in terms whereof he is renting a house from her. After the lease has been running for a few months, they agree orally that, from now on, Naomi (the lessor) shall pay for a gardening service to maintain the garden. In return, Joe (the lessee) will pay an extra N$ 100 in rent, since he no longer has to take responsibility for looking after the garden. Is this change valid? (4) 6.2 At a coffee shop on the 30th of April 2007, Freddy, a licensed diamond dealer, entered into a contract with Sylvia for the purchase and sale of 10 twenty one carat diamonds at a purchase price of N$ 25 000. It is agreed between the parties that Freddy will deliver the 10 diamonds to Sylvia on the 2nd of May 2007. When Freddy returned to his shop in order to package the diamonds he discovered that he had insufficient stock to meet his obligations in terms of the contract as he only had 2 twenty one carat diamonds in the safe. On the day of delivery he advised Sylvia that the contract is void because it is impossible for him to perform and as such not liable. Advise Sylvia whether or not Freddy is correct about the status of their contract. (6)