(b) If the member is totally disabled, the member shall receive ninety percent of his or her average full monthly compensation for the twelve-month contributory period preceding the member's disability award, or the shorter period if the member has not worked twelve months.
(c) If the member is partially disabled, the member shall receive forty-five percent of his or her average full monthly compensation for the twelve-month contributory period preceding the member's disability award, or the shorter period if the member has not worked twelve months.
(d) If the member remains partially disabled until attaining sixty years of age, the member shall then receive the retirement benefit provided in sections eleven and twelve of this article.
(e) The disability benefit payments will begin the first day of the month following termination of employment and receipt of the disability retirement application by the Consolidated Public Retirement Board.