Suppose that an oligopolistic is charging $21 per unit of output and selling 31

Suppose that an oligopolistic is charging $21 per unit of output and selling 31 units each day. What is its daily total revenue? Also suppose that previously it had lowered its price from $21 to $19 rivals matched the price cut and the firms sales increased from 31 to 32 units. It also previously raised its price from $21 to $23 rivals ignored the price hike and the firms daily total revenue came in at $482. Which of the following is most logical to conclude? The firms demand curve is(a) inelastic over the $21 to $23 price range(b) elastic over the $19 to $21 price range(c) a linear(straight) down sloping line or (d) a curve with a kink in it?