At its first meeting of each year, the council shall elect a president and vice-president from its membership. In the mayor's absence from a council meeting, the president, or in the president’s absence the vice-president, shall preside over it, but shall retain the right to vote on each question. In any event, the president or vice-president may vote only once on each question before the council. Whenever the mayor is unable to perform the other functions of the office, the president, or in the president’s inability the vice-president, shall act as mayor.