Need some help in answering a problem question - Equity & Trusts

Philip, who has just died, was a successful business man with a valuable collection of antiques and oil paintings. He owned several boats, including a yacht and a power boat and was also the owner of riding stables which he ran as a business. The stables housed 15 horses belonging to him. His will made in October 2000 contains the following dispositions:

a. my most valuable antiques to such of my boating friends as my trustees shall select;

b. one of my boats to my sister Jan, whichever she shall select, and the other to my sister, Katie;

c. my art collection and my horses to my wife, Susan. I direct her to sell all the paintings and use the money to maintain my horses for the rest of their natural lives. If there is any money left over, I’d like her to use it for a useful memorial to myself;

d. the remainder of my estate to my trustees upon trust for them to apply for the benefit of the citizens of Birmingham.

Consider the validity of the above dispositions.