What are three ways the narrator of "The Leap" owes her existence to her mother? What literary techniques are used to reveal this?

All of the three are presented through the literary technique of flashback, in which the narrator looks backwards in time and identifies the way that her mother Anna engaged in acts that directly led to her daughter's existence. The are told in a stream-of-consciousness style in the first person. 

The first leap is a physical one. As the mother was performing on a trapeze, blindfolded, lightning struck the main pole of the circus tent, causing the tent and trapeze to collapse. Anna grabbed a wire and managed to save herself from falling and dying with her husband.

The second leap was her marriage to a doctor, the narrator's father. The narrator's mother leapt metaphorically away from her familiar environment of the circus. In making this leap, she also learned to read, a great intellectual leap as she had previously been illiterate, and one that ignited in her a lifelong love of reading.

The third leap is the one Anna took from a tree to save her daughter, who was trapped in an upstairs bedroom, from a house fire.