Answer:
I can certainly help you analyze the passage. Let's break it down:
1A. The author's purpose for including the dialogue between Mr. and Mrs. Harris in paragraphs 2-5 is to establish miscommunication as a central theme for the passage.
1B. To identify the subsequent paragraph that most explicitly develops the answer to Part A, we'll need to review the content of the paragraphs. Without the text, I can't determine which paragraph specifically follows this development. Please provide the content of the paragraphs, and I can assist further.
2A. In paragraph 7, Mrs. Harris thinking that Mr. Harris will "spring to earth on reaching the summit and lean in a careless and graceful attitude against the machine, waiting for her" reveals that she is less adventurous than Mr. Harris.
2B. The quotation from paragraph 7 that supports the answer to Part A is: "... she saw him pass the summit and proceed rapidly down a long and steep incline ..."
3A. The interactions Mrs. Harris has with the Dutch characters in paragraph 7 likely help advance the plot by highlighting cultural differences and perhaps creating a situation that leads to further miscommunication or misunderstandings between the characters. The specifics would depend on the content of paragraph 7.