做一个无盖的正方体玻璃鱼缸，棱长4分米，制作这个鱼缸至少需要用多少平方分米的玻璃
题型：解答题
问题：
做一个无盖的正方体玻璃鱼缸，棱长4分米，制作这个鱼缸至少需要用多少平方分米的玻璃？
题型：解答题
Better think twice before choosing a password for e-mail, online bank or shopping. Simple passwords are easy to be stolen.
A password is like a key to your home. If someone steals it, he’ll get chances to steal something else. We use passwords everywhere in our life. We are so used to passwords that we don’t pay any attention to them until we lose or forget one.
A study of 28,000 passwords recently stolen from a popular website showed that people often do the easy thing. It found that 16 percent took a first name as a password. Another 14 percent used the easiest keyboard combinations such as “12345678” or QWERTY. Five percent of the stolen passwords were names of television shows or stars popular with young people. Three percent of the passwords expressed feelings like “I don’t care,” “Whatever,” “I love you,” or their opposite, “I hate you.”
Robert Graham, who did the study, advises people to choose a password that is longer than eight characters with one capital letter(大写字母) and one symbol.
Of course, safe passwords don’t mean those hard to remember. Forgetting your password is sometimes a big headache for you. Maybe, the perfect password is easy for you and hard for others.
小题1: The underlined word “password” in Paragraph 1 means __________.
A．标志
B．护照
C．密码
D．口诀小题2:About 40% passwords are easily stolen because the users are ______.
A．busy
B．lazy
C．stupid
D．careful小题3:Which of the following passwords is considered the safest?
A．ZXCVBN.
B．password56.
C．wy64#0Mv.
D．I hate you.