Please help me with this question! These sentences are from an English exercise, "The Merston City Careers Counseling service, in association with the Merston City Board of Education, would like to ask all Merston City High schools to join the "Stay in School campaign." Taking part is simple. Please display the posters in your classrooms." And the question is "Where will the posters be displayed?" and the answer is: In Merston City high school classrooms. I'm not quite satisfied with this answer as "Merston City high school classrooms" give me the impression that they want to display the posters in all classrooms at a high school called Merston City. To precisely, it should be: in Merston City high schools' classrooms. Is this correct? Or does "Merston City high school classrooms" already mean what I've said. Thank you very much for your kind help!