1 How long do you live in HN

2 How often did you go to the movies

3 What did Mrs Robinson buy

4 When was your father in Nghe An

5 How do they go to school

6 Why didn't she go to class

7 Who left home at 7o'clock yesterday

8 What subject does he study in the high school

9 What is your favorite hobby

10 How far is it

PTHH: \(Zn+2HCl\rightarrow ZnCl_2+H_2\uparrow\)

            \(FeO+H_2\xrightarrow[]{t^o}Fe+H_2O\)

Ta có: \(n_{Zn}=\dfrac{6,5}{65}=0,1\left(mol\right)=n_{H_2}=n_{Fe}\) \(\Rightarrow m_{Fe}=0,1\cdot56=5,6\left(g\right)\)

a/ \(\left(x-3\right)^2+6\left(x-3\right)+9\)

\(=\left(x-3\right)^2+2.\left(x-3\right).3+3^2\)

\(=\left(x-3+3\right)^2=x^2\)

==========

b/ \(\left(x+2021\right)^2+2\left(x+2021\right)\left(x-2021\right)+\left(x-2021\right)^2\)

\(=\left(x+2021+x-2021\right)^2=4x^2\)

===========

c/ \(2022^2-2.2021.2022+2021^2\)

\(=\left(2022-2021\right)^2=1\)

==========

d/ \(\left(x+44\right)^2-88\left(x+44\right)+1936\)

\(=\left(x+44\right)^2-2.\left(x+44\right).44+44^2\)

\(=\left(x+44-44\right)^2=x^2\)

d: Ta có: \(\left(x+44\right)^2-88\left(x+44\right)+1936\)

\(=\left(x+44-44\right)^2\)

\(=x^2\)

1. commuity service is work done by a person or group of people that benifits others

2. it is often done near the area where you live , so your own community gets the benifits work

3. no

4. community service can help many difference group of people , even animal and the inviroment 

5. community service is often organized through a local group , such as a place of worship , school , or non- profit organization , or you can start your own community service project .

6.community service can even involve raising funds by donating used goods or selling used goods like clothing 

dài vãi

quá dài

\(\left(\dfrac{1}{1.3}+\dfrac{1}{3.5}+...+\dfrac{1}{13.15}\right).x=\dfrac{-26}{45}\\ \Leftrightarrow\left(\dfrac{2}{1.3}+\dfrac{2}{3.5}+...+\dfrac{2}{13.15}\right).x=\dfrac{-52}{45}\\ \Leftrightarrow\left(1-\dfrac{1}{3}+\dfrac{1}{3}-\dfrac{1}{5}+...+\dfrac{1}{13}-\dfrac{1}{15}\right).x=\dfrac{-52}{45}\\ \Leftrightarrow\left(1-\dfrac{1}{15}\right).x=\dfrac{-52}{45}\\ \Leftrightarrow\dfrac{14}{15}.x=\dfrac{-52}{45}\\ \Leftrightarrow x=-\dfrac{26}{21}\)

(11.3+13.5+...+113.15).x=−2645⇔(21.3+23.5+...+213.15).x=−5245⇔(1−13+13−15+...+113−115).x=−5245⇔(1−115).x=−5245⇔1415.x=−5245⇔x=−2621