**Trả lời:
\(\left(-\frac{20}{3}\right)^3\cdot\left(-\frac{18}{5}\right)^2\)
\(=\left(-\frac{8000}{27}\right)\cdot\frac{324}{25}\)
\(=3840\).

\(\left(-\frac{20}{3}\right)^3\cdot\left(-\frac{18}{5}\right)^2\)

\(=-\frac{20^3}{3^3}\cdot\frac{18^2}{5^2}\)

\(=\frac{-\left(2^2\cdot5\right)^3}{3^3}\cdot\frac{\left(2\cdot3^2\right)^2}{5^2}=\frac{-2^6\cdot5^3}{3^3}\cdot\frac{2^2\cdot3^4}{5^2}\)

\(=-2^8\cdot5\cdot3=-256\cdot15=-3840\)

It is important for teenagers to join community service activities because it helps them become more responsible and caring individuals. Through these activities, they can gain useful skills like teamwork and communication, make new friends, and better understand the needs of their community. Community service also allows teenagers to experience the joy of helping others, which can increase their confidence and happiness.

Helping out in your community is super helpful, not just for others but for you too! First, it's a great way to understand how other people feel and be kind. When you help someone who's having a tough time, you'll learn to appreciate what you have and want to share more.Also, joining these activities helps you get better at important skills. Things like working with a team, talking clearly, and solving problems. Maybe you're helping clean up a park or spending time with older people. All these real experiences make you smarter and help you grow. Best of all, helping others makes you feel happy and useful. It's a cool way to make the world a better place, and it feels good to give back!

B. spread (lây lan)

Đáp án B nha bạn.

3)

Để \(\frac{x-7}{x-11}<0\rArr\left[\begin{array}{l}\begin{cases}x-7<0\\ x-11>0\end{cases}\\ \begin{cases}x-7>0\\ x-11<0\end{cases}\end{array}\right.\)

Trường hợp 1:

\(\frac{x-7}{x-11}>0\rArr\begin{cases}x-7<0\\ x-11>0\end{cases}\rArr\begin{cases}x<7\\ x>11\end{cases}\)

\(\rArr\) \(x\) không xác định

Trường hợp 2:

\(\frac{x-7}{x-11}>0\rArr\begin{cases}x-7>0\\ x-11<0\end{cases}\rArr\begin{cases}x>7\\ x<11\end{cases}\)

\(\rArr7

4)

\(\frac{x-9}{x-11}>0\rArr\left[\begin{array}{l}\begin{cases}x-9<0\\ x-12<0\end{cases}\\ \begin{cases}x-9>0\\ x-12>0\end{cases}\end{array}\right.\)

Trường hợp 1:

\(\frac{x-9}{x-12}>0\rArr\begin{cases}x-9<0\\ x-12<0\end{cases}\rArr\begin{cases}x<9\\ x<12\end{cases}\)

\(\rArr x<9\)

Trường hợp 2:

\(\frac{x-9}{x-12}>0\rArr\begin{cases}x-9>0\\ x-12>0\end{cases}\rArr\begin{cases}x>9\\ x>12\end{cases}\)

\(\rArr x>12\)

Vậy \(x<9\) hoặc \(x>12\)

Để \(\frac{-10}{x+7}\) âm thì \(x+7>0\)

\(\rArr x>-7\)

Vì tử số là -10 nên mẫu số phải là số dương

mà mẫu là x+7>0

=>x>-7

Vậy x>-7 thì \(- \frac{10}{x + 7}\) là số hữu tỉ âm

1. ✔

2. ✘ ➞ What about getting a cleaner to wash your clothes?

3. ✘ ➞ I don't like ironing, so I have a woman do it for me.

4. ✔

5. ✘ ➞ Why haven't you had your films developed yet?

1 to cut => cut

2 wash => to wash

3 to do => do

4 đúng

5 develop => developed

1. ✔

2. ✘ ➜ Have you had a meal prepared for you?

3. ✘ ➜ We are having the trees in the garden cut down.

4. ✘ ➜ Ron is going to have his house repainted after the summer vacation.

5. ✘ ➜ When are you going to have the curtain washed?

1 đúng

2 prepare => prepared

3 cutting => cut

4 repainted his house => his house repainted

5 wash => washed

1. ✔

2. ✘ ➜ Have you had a meal prepared for you?

3. ✘ ➜ We are having the trees in the garden cut down.

4. ✘ ➜ Ron is going to have his house repainted after the summer vacation.

5. ✘ ➜ When are you going to have the curtain washed?

1 đúng 2 prepare => prepared 3 cutting => cut 4 repainted his house => his house repainted 5 wash => washed

Từ này được mượn từ tiếng Hán, tức là ngôn ngữ tiếng Trung nhé.

Từ "giao tiếp" là một từ Hán Việt, tức là một từ mượn gốc từ tiếng Hán (tiếng Trung Quốc).