(a) No. In this case, although there is clearly agreement on the essential terms of a transaction, the purchase is made conditional on an event that may or may not happen - the buyer getting a loan at normal market rates. Until this condition is fulfilled, no contract comes into existence.
When no time is laid down within which the condition is to be fulfilled, it must be met within a reasonable time. If the condition is not fulfilled within the time allowed, no contract is made.
Generally, the parties to a conditional agreement are obliged to do whatever they may have promised, to bring about the fulfilment of a condition, or, if nothing in particular was promised, to do what is reasonably required.
Remember that the courts distinguish cases in which the performance, rather than the creation, of a contract is made conditional on the occurrence of some future event. An example of this type of case is: