(a) Personal representatives, as defined in section one, article one, chapter forty-two of this code, shall be allowed any reasonable expenses incurred by the personal representative as such and commissions upon the amount of all the personal estate which is subject to administration, including the income from the personal estate, that is received and accounted for by them and upon the proceeds of real estate that is sold, as follows:
(1) For the first $100,000, at the rate of five percent;