美食纪录片《舌尖上的中国》这样描写时间的味道：时间是食物的挚友，也是食物的死敌。”对“时间的味道”的描述说明（    ）

①矛盾双方是既对立又统一的关系

②矛盾的同一性寓于斗争性之中

③量的积累到一定程度会引起质变

④矛盾的普遍性离不开矛盾的特殊性

已知某两种物质在一定条件下能发生如下图所示的反应，则下列说法正确的是

（说明：一种小球代表一种元素的原子）

材料一

材料二

有甲、乙两位同学，根据“关于x的一元二次方程kx²﹣（k+2）x+2=0”（k为实数）这一已知条件，他们各自提出了一个问题考查对方，问题如下：

甲：你能不解方程判断方程实数根的情况吗？

乙：若方程有两个不相等的正整数根，你知道整数k的值等于多少吗？请你帮助两人解决上述问题．

It's important to teach children to create strong passwords（密码），and to remind them that passwords mustn't be shared with anyone, not even best friends.

A strong password is a word that is as difficult as possible to guess because it looks like a set of random characters （随机的字符）.

It's wise to use the whole keyboard to mix a password with letters, numbers and symbols. A password of 14 characters or more may be much safer.

The following tips will tell you how to create a strong and safe password:

Tip 1: Think of a sentence that is easy to remember, but difficult to guess. For example: “ My son Peter is five years old and my daughter Tina is one year old.”The whole sentence is so long that it can't be a password, so what you can do is to use the first letter of each word to make a new password that seems to be meaningless. That is “mspifyoamdtioyo”.

Tip 2: Make the password more difficult to guess by mixing big and small letters. One way to do this is to use big and small letters one after another. In this way this new password will be “MsPiFyOaMdTiOyO”.

Tip 3: Still using the sentence above, you can also add numers that are meaningful to you. As a result, the new password will be “Mspi5yOaMdTi1yO”.

Tip 4: Add punctuation（标点符号）and symbols to make the password much stronger. You may use symbols, numbers and punctuation to replace some letters which look similar. For example: “MsPi3y0@MdTi!y0”.(o=0, a=@, 1=!)

任务型阅读。根据材料内容，按要求完成下列各题。