(a)      A subscription for stock of a corporation which is not yet formed is irrevocable for a period of three months, unless:

            (1)      The subscription agreement provides otherwise; or

            (2)      Every subscriber consents to the revocation of the subscription.

      (b)      Unless the subscription agreement provides otherwise, a subscription is not void or unenforceable solely because less than all of the authorized stock is subscribed for.

      (c)      (1)      Unless the subscription agreement provides otherwise, a subscription for stock, whether made before or after the corporation is formed, shall be paid in full or in installments at the times set by the board of directors.

            (2)      The corporation shall give at least ten days written notice of the amount, time, and place of payment to each subscriber at his address as it appears on the records of the corporation.

            (3)      Any call made by the board of directors for payment on subscriptions shall be uniform as to all stock of the same class.