(a) If the commissioners deem best, they shall deposit the funds of the district in a solvent bank which will pay interest at not less than three percent (3%) nor exceeding four percent (4%) and shall give a good bond, conditioned that the funds shall be safely kept and paid out in accordance with the law.
(b) The order shall relieve the treasurer and his bondsmen from liability for loss of the funds through the insolvency of the bank and its bondsmen, and no commission shall be paid the treasurer on sums so deposited. The bank shall pay out the funds only on warrants drawn upon it as prescribed for funds in the hands of the treasurer.