giúp mìnhhh vớii
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1 Tom asked which book I had taken
2 I asked her when she was coming back
3 Mary asked when I had telephoned my mother
4 Ann asked how long the train took
5 She asked how far I had to walk
6 He asked what I was doing
7 The teacher asked him why he was so late
8 We asked what time the plane arrived
9 My father asked me why I hadn't phoned
10 He asked her where she stayed in Paris
11 My father asked me who I had seen at the meeting
12 I asked her where she was going
13 He asked me how I was
14 She asked how I had gone to school
15 Ann says he was tired
16 Tom said New York is bigger than London
17 I asked him where he had put it
18 They asked where my school was
19 Bill asks me where he will go tomorrow
20 Mary asked me when I had picked Ann up
21 John asked when the teacher would get back
22 William said he wouldn't visit her again
23 John said he had finished studying his lesson
24 The man said the clock would never work again if I tried to repair it
25 Mary told John she couldn't go to the movies with him
Lưu ý lần sau chia nhỏ bài ra hỏi để nhận dc sự giúp đỡ nhanh nhất nhé
uses crt;
var st:array[1..100]of string;
a,b,c:array[1..100]of real;
i,n:integer;
max:real;
begin
clrscr;
readln(n);
for i:=1 to n do readln(st[i],a[i],b[i],c[i]);
max=(a[1]+b[1]+c[1])/3;
for i:=1 to n do
if (max<(a[i]+b[i]+c[i])/3) then max:=(a[i]+b[i]+c[i])/3;
writeln(max:4:2);
readln;
end.
\(Cl_2+H_2\rightarrow2HCl\)
\(Zn+2HCl\rightarrow ZnCl_2+H_2\)
\(ZnCl_2+Ba\left(OH\right)_2\rightarrow Zn\left(OH\right)_2+BaCl_2\)
\(Zn\left(OH\right)_2+2HCl\rightarrow ZnCl_2+2H_2O\)
Cl2+H2→2HClCl2+H2→2HCl
Zn+2HCl→ZnCl2+H2Zn+2HCl→ZnCl2+H2
ZnCl2+Ba(OH)2→Zn(OH)2+BaCl2ZnCl2+Ba(OH)2→Zn(OH)2+BaCl2
Zn(OH)2+2HCl→ZnCl2+2H2O
Nếu đề hỏi nhận định nào sai thì đáp án D là nhận định sai, vì theo đề thì $c$ là phần tử nằm trong tập hợp M
\(a) Fe + 2HCl \to FeCl_2 + H_2\\ b) n_{Fe} = n_{H_2} = \dfrac{2,24}{22,4} = 0,1(mol)\\ m_{Fe} = 0,1.56 = 5,6(gam)\\ n_{Cu} = 12-5,6 = 6,4(gam)\)
a: \(\widehat{xOm};\widehat{nOm}\)
\(\widehat{nOm};\widehat{yOn}\)
\(\widehat{yOn};\widehat{xOn}\)
\(\widehat{xOm};\widehat{yOm}\)
b: \(\widehat{yOn};\widehat{xOn}\)
\(\widehat{xOm};\widehat{yOm}\)
c: \(\widehat{mOy}=180^0-30^0=150^0\)
\(\widehat{nOx}=180^0-50^0=130^0\)
\(\widehat{mOn}=180^0-80^0=100^0\)
\(\left\{{}\begin{matrix}\overrightarrow{AB}=\left(4;-7\right)\\\overrightarrow{BC}=\left(4;8\right)\\\overrightarrow{AC}=\left(8;1\right)\end{matrix}\right.\) \(\Rightarrow\overrightarrow{BC}+\overrightarrow{AC}=\left(12,9\right)\)
\(\Rightarrow\overrightarrow{AB}.\left(\overrightarrow{BC}+\overrightarrow{AC}\right)=4.12-7.9=...\)
b. Gọi \(H\left(x;y\right)\Rightarrow\left\{{}\begin{matrix}\overrightarrow{AH}=\left(x+3;y-5\right)\\\overrightarrow{BH}=\left(x-1;y+2\right)\\\end{matrix}\right.\)
Do \(AH\perp BC\Rightarrow\overrightarrow{AH}.\overrightarrow{BC}=0\)
\(\Rightarrow4\left(x+3\right)+8\left(y-5\right)=0\)
\(\Rightarrow x+2y=7\) (1)
Do H thuộc BC \(\Rightarrow\dfrac{x-1}{4}=\dfrac{y+2}{8}\Rightarrow2x-y=4\Rightarrow y=2x-4\)
Thế vào (1) \(\Rightarrow x+2\left(2x-4\right)=7\Rightarrow x=3\Rightarrow y=2\)
\(\Rightarrow H\left(3;2\right)\)