Lines 33–43:What techniques are being used to build tension in these lines in story the leap

"I owe her my existence three times. The first was when..." uses words that is used to shift the tense from present to past. This shows that the author is trying to explain her debt to her mother. "I have lived in the West..."  uses words that is used to shift the tense to past, the author tries to explain about  her own personal adult life.

Explanation:

"I owe her my existence three times. The first was when..." uses words that is used to shift the tense from present to past. This shows that the author is trying to explain her debt to her mother. "I have lived in the West..."  uses words that is used to shift the tense to past, the author tries to explain about  her own personal adult life. This statement builds up tension because the audience knows that the narrator is about say an anecdote. The anecdote connects how she owes her life to her mother.

you didn't list the options but im guessing it's resolving contradictions

- the heat nearly killed them that first summer.