Comment briefly on the provisions described in these instruments as to their bearing on negotiability. In each instance, the other portions of the instrument are in proper form.

a. A bill of exchange drawn by Y on Z directs Z to pay $1,000 to the order of A and charge this amount to Y's "Book Fund."

b. The XYZ Company (a partnership) signed a note promising to pay $1,000 and bearing the notation "limited to payment out of the entire assets of the maker."

c. X signed a note promising to pay $5,000 or deliver 100 barrels of oil at the option of the holder.

d. One of the notes is payable "five days after the death of the maker."

e. A note containing the following notation: "with interest at bank rates."