图为肾蕨，据图回答（中填写图中数字）：

（1）图中的地上部分是____ ____，地下部分是____ ƒ____和____ ____ ．

（2）成熟的孢子囊内有____  它与肾蕨的繁殖有关，因此，肾蕨属于____ 中的蕨类植物．（选填“孢子植物”或“种子植物”）

    Workers aren't allowed to go into a big underground computer center until they step up to a machine that takes a quick picture of the tiny blood vessels (血管) inside their eyes.

    If the machine can't 1 the picture with images in its computer, the worker is stopped by security guards (保安员).

    Each person has his own way of blood vessels in his or her2.And unlike a key, the way can't be3.Old-fashioned keys and locks may soon be things of the past.High-tech security devices (安全装置) are being fixed at military (军事的) bases, computer centers and banks.Companies that 4 the machines say they'll someday be used in people's homes and cars.

    Already, a Japanese company has fixed ways that recognize (识别) people's fingerprints in 360 new homes.The machines open the doors only for the 5of the houses.The new security ways are selling well because thieves and robbers are getting better at breaking into buildings and computers that are 6 by keys and locks.Since nobody can steal or copy a fingerprint, or one's eyes, the new machines are 7.

    Other new machines recognize one's voice.Two American companies use 8 machines to keep an eye on their computers.Inexpensive voice-recognition machines may someday take the place of locks on cars.The doors would open only for the owners.The machines would 9 the owners as little as $270.Although the up-to-date machines are amazing, scientists must still solve a serious problem.How will a boy borrow his dad's car without borrowing his dad's 10?

下列（        ）是国家生活中最根本的问题。

分布于我国地形第二阶梯上的最主要两种地形为（　　）