(1) The sum payable by a bill is a sum certain within the meaning of this Act, although it was required to be paid -
(a) With interest.
(b) By stated instalments.
(c) By stated instalments, with a provision that upon default in payment of any instalment the whole shall become due.
(d) According to an indicated rate of exchange or according to a rate of exchange to be ascertained as directed by the bill.
(2) Where the sum payable is expressed in words and also in figures, and there is a discrepancy between the two, the sum denoted by the words is the amount payable.
(3) Where a bill is expressed to be payable with interest, unless the instrument otherwise provides, interest runs from the date of the bill, and if the bill is undated from the issue thereof.