Bài 4: Có 5 công nhân làm trong 3 ngày , mỗi ngày làm 8 giờ làm được 24 sản phẩm. Hỏi 7 công nhân làm trong 4 ngày, mỗi ngày làm 10 giờ thì làm được bao nhiêu sản phẩm. (Biết năng xuất của mỗi công nhân là như nhau.)

1)……………..call for the ………………of the countryside.( conserve ) 2) People must learn about keeping the environment ………………(pollute) 3) It was very ……of you to leave the medicine where the children could get it.(care) 4) Environmental groups want a total…..on the dumping of nuclear waste.( prohibit) 5) I am ……………..that people have spoiled this area.(disappoint) 6) They are meeting to find ways to protect the forests from……………(forest). 7) The……….of computers is one of the recent……in our time (invent-achieve) 8) The ………….to the problem will be difficult to find.( solve) 9) The news has caused …………………among scientists.( excite) 10) Thanks a lot for your…………….help. (value) 11) Rain will reach……………………areas at the end of this week.(coast) 12) Many ………………walked around the tourist attraction to take photos.(sight) 13) Thanks to …….conservationists, many kinds of plants and animals are protected. ( enthusiasm) 14) It is……………….that some people poach fish in the Nhieu Loc Canal.(disappoint) 15) We are worried that rivers and canals are becoming more and more ……( pollute) 16) The……………were disappointed that people had spoiled the area. (environmental) 17) In order to keep our environment………..…, we shouldn’t drop litter in public places (pollute) 18) Don’t pump……………. into seas and rivers or it will pollute them (sew) 19) If we keep on... the air, more people will suffer from respiratory diseases (pollution) 20) The local authorities have received many letters of………. about the industrial wastes from that factory (complain)

phát biểu nào sau đây đúng và giải thích tại sao các đáp án còn lại sai ?

Bài 3: Tìm chữ số tận cùng của tích sau: 11x13x15x17x19x .... x2019

Ai giúp mk với ......................

1. Cho pt : x^2 - 2(m+1)x + 2m + 1 = 0 (1) . Tìm các giá trị cùa m để pt (1) có 2 nghiệm x1,x2 sao cho -1<x1<=x2<2 2. Một ăng-ten chảo dạng Parabol có h=0,5m và d=4m . Ở mặt cắt qua trục ta được 1 Parabol có dạng y=ax^2. Hãy xác định hệ số a.

Giúp mình vs ạ. Mình gấp lắm. Mình vote 5*

1.I watch the news every day because it’s very ……………(inform) 2. I enjoy the constant ………………with students from other classes ( interact) 3.The ………………of the magazine has declined since last year.(popular) 4.The newspaper is ……………….read by both teenagers and adults.( wide) 5.There is an………………….documentary on Channel 4 tonight.( interest) 6) The next stage in the……………….of television is interactive TV.(develop) 7)It would be more………………..to switch the machine off at night( economy) 8) This book is cheap. It’s……………….. (expensive) 9) ……………….. TV is avaible now (interact) 10) She is a ……………..girl. (communicate) 11) The ……………. between this computer and the others is good (interact) 12) Listen……………….., please (care) 13) They said ‘good bye’ to each other just because of some minor …… . (understand) 14) Make sure that your time is spent……………..(use) 15) The…………… of people interviewed prefer Tv to radio (major) 16) Kien Thuc Ngay Nay is one of the most…………… magazines (popularity) 17) The website is not used for teenagers. It’s …………….(use) 18) He is old. He’s getting forgetful, and his ……often makes a lot of trouble. ( forget ) 19) Their …………………… is always good (communicate) 20) I can’t believe you, what you say is quite…………... ( logic )

Bài 2: Tính nhanh ( 43 x 11 + 44 x 11 + 45 x 11 + 46 x 11 + 47 x 11) : (45 x 55)

Cho phương trình bậc hai x^2 - 2( m-1)x - 4m = 0. Phương trình vô nghiệm khi: A. m ≤ -1 B. m ≥ -1 C. m > - 1 D. Một đáp án khác