One day a girl gets a package in the mail. It contains US$3,000___31__cash and a letter from ‑­her late (去世的) Aunt Peg. Aunt Peg has something useful to pass __32___to her niece, but a rather unusual way of going about it. The girl __33___ (give) a set of instructions: "Go to an address in New York and pick up a package, get a passport and buy yourself a one-way ticket to London." ___34___ she flies she is told to make sure she only takes ___35___she can fit into a backpack. No money, credit cards, camera. No mobile phone ___36____ laptop. And once she gets to Europe she can't call or even e-mail home. On the plane, Ginny opens the New York package. It sends her to a flat in London where a man___37__ (name) Richard seems to be expecting her.

This is __38____ US author Maureen Johnson's hit teen novel, "13 Little Blue Envelopes" opens. ___39____ heroine (女主人公) is Ginny, a quiet, 17-year-old girl , __40___ has a great adventure ahead of her.

在需要均匀调速的生产机械中或在电力牵引中，一般采用（）。

A.鼠笼式三相异步电动机

B.绕线式三相异步电动机

C.直流电动机

D.交流同步电动机