Giúp e 3 bài này với 10h e phải nộp r e cảm ơn ak!

1+2-2+3-3+...+1099-1098+1020 bằng mấy vậy.

What is your choice for further education ? Why ?

"Đã là bạn thì mãi mãi là bạn Đừng như sông lúc cạn lúc đầy" là ca dao hay tục ngữ giúp tớ nhé cảm ơn

Câu 1 : Cho x + 2y = 1. Tính giá trị của biểu thức A = x2 - 4y2 + 4y. Câu 2 : Tính giá trị của biểu thức: D= x^4-3x^3+18x-1/x^3-2x^2+7x-1 với x/x^2-x+1=1/2 .

Giúp mik bài V đi.Mik sẽ cho 5 sao nếu trả lời đúng

Cọ xát 2 vật khác nhau 1 thời gian. Nếu các vật bị nhiễm điện thì chúng nhiễm điện như thế nào. Giải thích ạ.

/x/ < 3 (X -3 ) .(X-5)<0 2x ²-3= 29 tìm x ạ giúp em ba phép tính này thôi ai nhanh nhất e cho câu trả lời hay nhất

2. She speaks English quite……………………………………. A. good B. bad C. fluently D. well 3. He shouted and looked …………………at me when I broke the vase. A.angry B. angrier C. anger D. angrily 4.If we go on littering, the environment will become....................... A. polluted B. pollution C. pollute D. polluting 5.Her parents were extremely pleased ……………….. she passed the exam.. A. that B.as C. while D. why 6.By sticking labels over the address you can ………………………..envelopes. A. revise B. repair C. reuse D. return 7. If we ______ less paper, we ………………………. trees in the forest. A. used/ will save B. will use/ save C. use/ can save D. uses/ will save 8.Ba is pleased ………………………his English is improving day-by-day. A. though B. that C. so D. but 9..Nam broke the glass …………………….he was careless. A. because B. which C. since D.A&C are correct 10.We must learn about keeping the environment……………….... A. clearly B. unpolluted C. polluted D. safely 11.My sister laughed………………………as she played with her doll. A. silly B. sadly C. happy D. happily 12. Our health ................................ worse if the pollution continues. A.is B. will is C. are D. will be 13.He shouted any looked ……………………… at me when I broke the vase. A. angry B. angrier C. angrily D. angrily 14.He is tired ………………………. he stayed up late watching TV. A. so B. because C. but D. and 15.Is he really …………………….. that you can’t come here? A. disappoint B. disappointed C. disappointing D. to disappoint 16.I think most children are creative enough to write ……………… poems. A. beauty B. beautiful C. beautifully D. beautify 17.It is our policy to ………………….. forests and increase forestation. A. protect B. protecting C. to protect D. protected 18.Everyone must take part in …………………… deforestation. A. prevent B. preventing C. to prevent D. prevented 19.They made their living by ………………. fish in the ocean every day. A. catch B. catching C. to catch D. caught 20. We can’t swim in this lake………………….the water is highly polluted. A. since B. but C. however D. All are correct

Cho 7,7(g) hh Mg, Zn + dd HCl dư —> 3,36 lít H2 ( đktc ) Tính thành phần % khối lượng mỗi KL trong hh