a)Điện trở dây: \(R=\rho\cdot\dfrac{l}{S}=1,1\cdot10^{-6}\cdot\dfrac{30}{0,2\cdot10^{-6}}=165\Omega\)

b)Công suất bếp: \(P=\dfrac{U^2}{R}=\dfrac{220^2}{165}=\dfrac{880}{3}W\)

c)Điện năng bếp tiêu thụ trong thời gian \(t=14ph=840s\) là:

\(A=UIt=\dfrac{U^2}{R}t=\dfrac{220^2}{165}\cdot840=246400J\)

1. prefer/ women/ often/ modern/ work/ today/ Vietnamese/ to/ / wear/ at.

……………Vietnamese women today often prefer to wear modern at work (thiếu từ phải ko bạn) ………………………………………………………………………

2. he/ hard/,/ so/ he/ /all/ his/ passed/ exams/ worked.

........He worked hard, so he passed all his exams............................................................................................................................

3. peaceful/ liked / while / Lan / praying/ the /atmosphere/ Maryam/ was.

………While Lan was praying, Maryam liked the peaceful atmosphere …………………………………………………………………………………

4. the/ water/ very/ was/ cold/, /so/ we/ swim/ couldn’t.

............The water was very cold, so we couldn't swim............................................................................................................................

5. I / arrive / Ha Noi Train station / 2 p.m / last Monday.

……I arrived at HN Train station at 2 p last monday……………………………………………………………………………………………

6. I / already / visit / lot / famous / places / Ha Noi.

 ………I have already visited a lot of famous places in HN……………………………………………………………………………………

7. I / really / impress / beauty of the city / by / friendliness / people..

…I was really impressed by the beauty of the city and by the friendliness of people………………………………………………………………………………………………..

8. I / return / home / next Friday.

………I will return home next Friday…………………………………………………………………………………………

9. bad/ She/ study/ got/ hard, / so/ didn’t/ marks/ she

=> …She didn't study hard, so she got bad marks…………………………………………………………………………………………

10. long/ you/ known/ How/ him/ have?

=> ………How long have you known him?………………………………………………………………………………………..

a.P: AA x aa
Gp A    a

F1 :KG Aa
KH 100% cao
F1xF1: Aa   x    Aa
GF1 : A,a         A,a
F2: KG1AA 2Aa 1aa

KH 3cao 1 thấp

b.

cho các cây thân cao F2 tự thụ, nếu đời con cho 100% cao => KG thuần chủng
nếu đời con phân li theo tỉ lệ 3:1 => KG dị hợp

AA XAA => 100%AA

Aa xAa => 3 A_ 1 aa
 

a: Vì \(a=1-\sqrt5<0\)

nên hàm số \(y=\left(1-\sqrt5\right)x-1\) nghịch biến trên R

b: Thay \(x=1+\sqrt5\) vào \(y=\left(1-\sqrt5\right)x-1\) , ta được:

\(y=\left(1-\sqrt5\right)\left(1+\sqrt5\right)-1\)

=1-5-1

=-5

c: Đặt \(y=\sqrt5\)

=>\(\left(1-\sqrt5\right)x-1=\sqrt5\)

=>\(\left(1-\sqrt5\right)x=\sqrt5+1\)

=>\(x=-\frac{\sqrt5+1}{\sqrt5-1}=-\frac{\left(\sqrt5+1\right)^2}{\left(\sqrt5-1\right)\left(\sqrt5+1\right)}=-\frac{6+2\sqrt5}{5-1}=-\frac{6+2\sqrt5}{4}=-\frac{3+\sqrt5}{2}\)

Ý nghĩa của chi tiết Vũ Nương gieo mình xuống sông tự vẫn:

- Phản ánh số phận của người phụ nữ trong xã hội xưa phải chịu oan khuất và uất ức mà đi đến bức đường cùng.

- Bày tỏ sự tiếc thương của tác giả trước số phận mong manh và đau khổ của người phụ nữ trong xã hội phong kiến.

- Tố cáo đanh thép xã hội phong kiến tàn ác bất nhân chà đạp lên quyền sống của người phụ nữ.

With the developments of our country,having a life skill play a vital part to teenagers in Vietnam.In my opinion,communication is one of the most important skills that they really need.First of all,in a modern world,communication is more neccessary,having this skill,youngsters can easily get a good job in the future.As i see,almost every one who is good at communicating achieve a great success in their lives.Secondly,this skill will make you feel more confident in front of crowd,so you can show your ability without any difficult.Everyone will also believe in you.Moreover,communication skill even help you to make friends.It's can't be denied that speech is the fastest way to connect people with each other.Therefore,the better you are at communicating,the more friends you will have.Inconclusion,in my point of view,communicating is a really vital life skill.