please i need i answer regarding microeco.multiple choices :

:If demand is inelastic, marginal revenue is :Select one a. Infinity b. Positive C. zero 0 0!. Negative 0 Suppose a firm is producing an output level .for which price exceeds average total cost From this information, which of the following ?can be deduced |. the firm is maximizing profits \"the firm is earning positive profits III. the firm is a price taker IV. the firm faces a downward sloping demand curve :Select one a. land || only O b. I and Illonly O c. lionly 0 d. H and IV only 0 .e. H and I\" only 0 The short-run market supply curve is derived :from :Select one a. the horizontal summation of each 0 firm's individual supply curve b. the horizontal summation of each 0 rm's marginal cost curve above the shutdown price c. profit-maximizing output decisions by 0 firms d. both a and c 0 e. all of the above 0