Answer:
for interest rates equal to or lower than 200%, the firms will use trigger strategies to support the collusive level of advertising
Explanation:
Using the below expression to determine the range of interest rates could these firms use trigger strategies to support the collusive level of advertising; we have:
[tex]\frac{current \ period's \ profit \ of \ the \ cheating \ firm \ - \ firm's \ profit \ in \ each \ period \ under \ collision }{ firm's \ profit \ in \ each \ period \ under \ collision \ - \ profit \ in \ each \ subsequent \ period \ of \ cheating \ firm } \leq \frac{1}{i}[/tex]
where;
[tex]the \ current \ period's \ profit \ of \ the \ cheating \ firm \ = \ 49[/tex]
[tex]firm's \ profit \ in \ each \ period \ under \ collision = \ 9[/tex]
[tex]\ profit \ in \ each \ subsequent \ period \ of \ cheating \ firm } = \ 1[/tex]
Then :
= [tex]\frac{49-9}{9-1} \leq \frac{1}{i}[/tex]
= [tex]\frac{40}{8} \leq \frac{1}{i}[/tex]
[tex]i \leq \frac{8}{40}[/tex]
[tex]i \leq 200[/tex]%
Thus; for interest rates equal to or lower than 200%, the firms will use trigger strategies to support the collusive level of advertising