Attention please . here is a ............special............ announcement . A little girl is reported missing . she was last seen 20 .........minutes.............. ago near the main entrance to the car fair. Her name's mary and she is three years old . she has .........short.............. dark hair . she 's wearing shorts blue shorts and along sleeved white ...........blouse.......... she 's wearing a pair of shoes the brown shoes . she may be carrying a large .......... doll.......... If you see mary , please bring her to the ...........information.............. desk , her father is waiting for her there

Attention, please. Here is a special announcement. A little girl is reported missing. She was last seen 20 minutes ago near the main entrance to the Car Fair. Her name's Mary and she is 3 years old. She has dark, short hair. She is wearing shorts, the blue shorts and a long-sleeved blouse. She is wearing a pair of shoes, th brown shoes. She may be carruing a large doll.

If you see Mary, please bring her to the the Information Desk. Her father is waiting for her there. Thanks.

*Questions:

1. How old is Mary?

=>she's 3 years old

2. Where does she lose her way?

=>near the main entrance to the Car Fair

3. What is she wearing?

=>She is wearing shorts, the blue shorts and a long-sleeved blouse. She is wearing a pair of shoes, th brown shoes. She may be carruing a large doll.

4. Where is Mary's father waiting for her?

=>the Information Desk

1. She is 3 years old

2.She has dark,short hair

3.She is wearing shorts , the blue shorts and long - sleeved blouse

4.Informatin Desk

1. Mary is 3 years old

2.She lose her way near the main entrance to the Car Fair

3. She wearing shorts, the blue shorts and a long-sleeved blouse. She is wearing a pair of shoes, the brown shoes.

4. Mary's father waiting for her at the Information Desk.

PTHH: \(Al_2O_3+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2O\)

Ta có: \(\left\{{}\begin{matrix}m_{H_2SO_4}=588\cdot5\%=29,4\left(g\right)\Rightarrow n_{H_2SO_4}=\dfrac{29,4}{98}=0,3\left(mol\right)\\n_{Al_2O_3}=\dfrac{20,4}{102}=0,2\left(mol\right)\end{matrix}\right.\)

Xét tỉ lệ: \(\dfrac{0,2}{1}>\dfrac{0,3}{3}\) \(\Rightarrow\) Al₂O₃ còn dư

\(\Rightarrow n_{Al_2\left(SO_4\right)_3}=0,1\left(mol\right)=n_{Al_2O_3\left(dư\right)}\)

\(\Rightarrow C\%_{Al_2\left(SO_4\right)_3}=\dfrac{0,1\cdot342}{20,4+588-0,1\cdot102}\cdot100\%\approx5,72\%\)

\(d,ĐK:x\ge1\\ PT\Leftrightarrow\sqrt{x-1}=2+\sqrt{x+1}\\ \Leftrightarrow x-1=2+x+1+4\sqrt{x+1}\\ \Leftrightarrow4\sqrt{x+1}=-4\Leftrightarrow x\in\varnothing\left(4\sqrt{x+1}\ge0\right)\\ g,ĐK:x\ge\dfrac{1}{2}\\ PT\Leftrightarrow x+\sqrt{2x-1}+x-\sqrt{2x-1}+2\sqrt{\left(x+\sqrt{2x-1}\right)\left(x-\sqrt{2x-1}\right)}=2\\ \Leftrightarrow2x+2\sqrt{x^2-2x+1}=2\\ \Leftrightarrow\sqrt{\left(x-1\right)^2}=\dfrac{2-2x}{2}=1-x\\ \Leftrightarrow\left|x-1\right|=1-x\\ \Leftrightarrow\left[{}\begin{matrix}x-1=1-x\left(x\ge1\right)\\x-1=x-1\left(x< 1\right)\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=1\left(tm\right)\\x\in R\end{matrix}\right.\)

Ha's house is small and it's in the country

Ha's house is small and It's in the country

^{_{Ha's house is small and It's in the country}}

I/ fill in the blanks with proper words

1. He is an (edit/ editor /edition /editorial) of the VietNam News office

2. This school has (excel /excellent /excellence /excellently) reputation

3. It was an (enjoy /enjoyment /enjoyable /enjoyably) day

4. He feeds the chickens and (collects/ collections/ collective / collectors) their eggs

5. They walked (to/ at/ in/ for) half an hour to reach the waterfall

6. They are going to hold SEA GAMES 23 (from/ in/ at/on) Philippines

7. The telephone was invented (with/ on/by/ from) Alexander Bell

8. He will be in Singapore from Monday (in/ up to/ at/on) Thursday

Bài 3.

Định luật ll Niu-tơn:

\(\overrightarrow{F}+\overrightarrow{F_{ms}}=m\cdot\overrightarrow{a}\)

\(\Rightarrow F-F_{ms}=m\cdot a\)

Gia tốc vật:

\(a=\dfrac{F-F_{ms}}{m}=\dfrac{4,5-\mu mg}{m}=\dfrac{4,5-0,2\cdot1,5\cdot10}{1,5}=1\)m/s²

Vận tốc vật sau 2s:

\(v=a\cdot t=1\cdot2=2\)m/s