Combine the senterces . Use the words in brackets.

1.He studied very hard .He failed the test(although)

=> Althought he studied very hard, he failed the test.

2.Her illness is serious.She doesn't see her .(despite)

=> Despite her illness is serious, she doesn't see her

3.She can work.It is very noisy.(Even though)

=> Even thought it is very noisy, she can work.

Giải:

Từ đẳng thức \(a+b+c=0\), ta có:

\(\left\{{}\begin{matrix}a=-b-c\\b=-a-c\\c=-a-b\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}b+c=-a\\a+c=-b\\a+b=-c\end{matrix}\right.\)

Thay vào từng biểu thức, ta được;

\(M=a\left(a+b\right)\left(a+c\right)\)

\(\Leftrightarrow M=a\left(-c\right)\left(-b\right)\)

\(\Leftrightarrow M=abc\) (*)

\(N=b\left(b+c\right)\left(b+a\right)\)

\(\Leftrightarrow N=b\left(-a\right)\left(-c\right)\)

\(\Leftrightarrow N=abc\) (**)

\(P=c\left(c+a\right)\left(c+b\right)\) (Sửa đề)

\(\Leftrightarrow P=c\left(-b\right)\left(-a\right)\)

\(\Leftrightarrow P=abc\) (***)

Từ (*), (**) và (***) \(\Rightarrow M=N=P\)

Vậy ...

không rastnneen ko chia hết

1, How about dinner at the Royal Restaurant this weekends with the old friends?

=> Having dinner
2, We are having a birthday party in Saturday night. Would you like to come?

=> On
3, Would you like going to the concert with my friends tonight?

=> To go
4, What about go to the cinema with our classmates this evening?

=> Going
5, They’re going to build a house new on this street.

=> New house
6, What do you going to do with the cellular phone?

=> Are
7, I’m going to traveling with my family this summer vocation.

=> Travel
8, Do you want go to the museum with us this Friday?

=> To go
9, Let me help you do the housework so that we can have time enough for our homework.

=> Enough time
10, She is carry the boxes of books upstairs with the help of one of her neighbors.

=> Carrying

Bài 2:

a) Số mol H2SO4 là:

nH2SO4 = C_M.V = 1,5.0,2 = 0,3 (mol)

PTHH: Al2O3 + 3H2SO4 -> Al2(SO4)3 + 3H2O

------------x---------3x-------------x------------3x--

PTHH: CaO + H2SO4 -> CaSO4 + H2O

----------y--------y-------------y-------y----

Gọi nAl2O3 = x (mol) và nCaO = y (mol)

Ta có hệ phương trình:

\(\left\{{}\begin{matrix}mAl2O3+mCaO=11,52\left(g\right)\\nH2SO4=0,3\left(mol\right)\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}102x+56y=11,52\left(g\right)\\3x+y=0,3\left(mol\right)\end{matrix}\right.\)

Giải hệ phương trình, ta được:

\(\left\{{}\begin{matrix}x=0,08\left(mol\right)\\y=0,06\left(mol\right)\end{matrix}\right.\)

Khối lượng mỗi oxit trong hỗn hợp là:

mAl2O3 = n.M = 102.0,08 = 8,16 (g)

=> mCaO = 11,52 - 8,16 = 3,36 (g)

b) Đề thiếu

Vậy ...

Số phần trăm các bạn đạt điểm giỏi là

25% + 30% = 55%

có \(\frac{B\left(5\right)}{B\left(9\right)}\)Còn lại tự đếm