In which one of the following circumstances can the condictio indebiti be used?

In order to be successful with a claim based on the condictio indebiti, the plaintiff must prove the following fact(s) or requirement(s):

X has concluded a contract with Y to build a tennis court at a cost of R40,000 on the property it is renting from Z in Pretoria. It can be shown that the value of the property has increased by R20,000 due to the improvement. X has disappeared before paying Y for the work done. Y now wants to lodge a claim against Z, the owner of the property.

Which statement best explains the ground on which and the amount that Y can claim?

Which statement correctly explains the possession or occupation of another's property?

A has demanded payment from B of an amount of R50,000 which he believes B is owing. B has checked its records and has paid the amount in the bona fide belief that the amount is owing in terms of their contract. Unbeknown to B, his bookkeeper, C had already paid the amount a week earlier by way of an electronic funds transfer into the account of A. At the time of the second payment A's account was overdrawn in the amount of R30,000 and was therefore in credit of R20,000 after the payment. A has taken R15,000 out of his account to pay his employees their monthly wages. He has also paid R10,000 for a luxury weekend after realising that his account was in credit.

Which statement regarding the requirements for an enrichment action is correct?

A has demanded payment from B of an amount of R50,000 which he believes B is owing. B has checked its records and has paid the amount in the bona fide belief that the amount is owing in terms of their contract. Unbeknown to B, his bookkeeper, C had already paid the amount a week earlier by way of an electronic funds transfer into the account of A. At the time of the second payment A's account was overdrawn in the amount of R30,000 and was therefore in credit of R20,000 after the payment. A has taken R15,000 out of his account to pay his employees their monthly wages. He has also paid R10,000 for a luxury weekend after realising that his account was in credit.

Which statement best explains the calculation of the enrichment claim?

G has noticed that his neighbour's (H) stud bull is seriously ill. The neighbour is currently on a hiking trip outside the country and cannot be reached. G has called out a veterinary doctor to attend to the bull and has paid all his bills as well as for the medication. The total cost was R12,000. Despite the treatment the bull has died. 

Which statement best explains the basis of G's possible claim against H?

A has demanded payment from B of an amount of R50,000 which he believes B is owing. B has checked its records and has paid the amount in the bona fide belief that the amount is owing in terms of their contract. Unbeknown to B, his bookkeeper, C had already paid the amount a week earlier by way of an electronic funds transfer into the account of A. At the time of the second payment A's account was overdrawn in the amount of R30,000 and was therefore in credit of R20,000 after the payment. A has taken R15,000 out of his account to pay his employees their monthly wages. He has also paid R10,000 for a luxury weekend after realising that his account was in credit.

Which statement best explains the nature of B’s claim against A?

G has noticed that his neighbour's (H) stud bull is seriously ill. The neighbour is currently on a hiking trip outside the country and cannot be reached. G has called out a veterinary doctor to attend to the bull and has paid all his bills as well as for the medication. The total cost was R12,000. Despite the treatment the bull has died. G is a meddlesome neighbour and H has previously warned him not to do anything on his farm under any circumstances, but rather to call K, if G should notice any problem. G did not bother to call K. 

Which statement best explains the basis of G's possible claim against H?

X has concluded a contract with Y to build a tennis court at a cost of R40,000 on the property it is renting from Z in Pretoria. It can be shown that the value of the property has increased by R20,000 due to the improvement. X has disappeared before paying Y for the work done. Y now wants to lodge a claim against Z, the owner of the property.

Which statement best explains the authority to substantiate the ground on which and the amount that Y can claim?