Can you help please

Profits of an industry incumbent are given by 1 = K1(90 - K1 - K2) and profits of a potential entrant are n2 = K2(90 - K1 - K2), where K1 and K2 represent capacities. a. Derive the value of K1 and K2 if the incumbent first chose capacity taking into account the future reaction of the entrant. [5 points] b. Derive the value of K1 and K2 in case both firms simultaneously decide capacity. [5 points] c. Compare answers in (a) and (b) explain why there is a "first-mover advantage." [5 points] d. Consider the sequential move game described in (a). Suppose now that the entrant bears a fixed cost of 100. Find its new reaction function. [5 points] e. Does the new reaction function in (d) imply that entry of firm 2 can be blockaded? Is the interest of the incumbent to "block" or to "accommodate" the entry? [5 points]