Chon D
Giai thich:
Do A, B là 2 biến cố xung khắc nên ta có: \(P_{\left(A\cup B\right)}=P_{\left(A\right)}+P_{\left(B\right)}=0,32+0,63=0,95\)

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vì độ lớn của điện tích âm là \(\) \(1,6.10^{-19}C\)

Bài 2:
Mạch điện gồm [\(R_1\) nt\(R_{}\) ]
\(R_{AB}=R_1+R=6+R\)
\(I_{AB}=I_{R}=\frac{U_{AB}}{R_{AB}}=\frac{12}{6+R}\)
Ta có: \(P_{R}=I_{R}^2.R\)
\(\rArr P_{R}=\left(\frac{12}{6+R}\right)^2.R\)
\(\rArr P_{R}=\frac{12^2}{\frac{6^2}{R}+R+2.6}\)
\(\rArr P_{R}=\frac{144}{\frac{36}{R}+R+12}\)
Ta thấy \(\frac{36}{R}+R\ge2.\sqrt{\frac{36}{R}.R}\)
\(\rArr\frac{36}{R}+R\ge2.6\)
\(\rArr\frac{36}{R}+R\ge12\)
\(\rArr\) Mẫu số \(\ge12+12\)
\(\rArr\) Mẫu số \(\ge24\)
\(\rArr P_{R}\max=\frac{144}{24}=6\lrArr\frac{36}{R}=R\lrArr R=6\Omega\)
Vậy \(P_{R}\max=6WkhiR=6\Omega\)

Bài 1:
Mạch điện gồm: [(\(R_1\) // \(R_2\) ) nt (\(R_3\) // \(R_4\) )]
\(R_{AB}=R_{12}+R_{34}\)
\(\rArr R_{AB}=\frac{2.3}{2+3}+\frac{4.6}{4+6}=1,2+2,4=3,6\left(\Omega\right)\)
\(I_{AB}=I_{12}=I_{34}=\frac{U_{AB}}{R_{AB}}=\frac{18}{3,6}=5\left(A\right)\)
\(U_{34}=U_3=I_{34}.R_{34}=5.2,4=12\left(V\right)\)
\(I_3=\frac{U_3}{R_3}=\frac{12}{4}=3\left(A\right)\)
Vậy \(I_3=3A\)

Ta có: \(E=\frac{U}{d}\)
\(\rArr E=\frac{0,08}{8.10^{-9}}=0,01.10^9\)
\(\rArr b=0,01\)
Vậy b=0,01

1. Mary/ tall/ her brother
-> Mary is taller than her brother. 2. This dress/ pretty/ that/ one.
-> This dress is prettier than that one.
3. the weather today/ cold/ yesterday. -> The weather today is colder than it was yesterday.
4. the weather yesterday/ hot/ today.
-> The weather yesterday was hotter than it is today.
5. Ba/ friendly/ Nam.
-> Ba is friendlier than Nam.
6. Your house/ far/ from school/ my house.
-> Your house is farther from school than my house.
7. A horse/ strong/ a person.
-> A horse is stronger than a person.
8. The Nile/ long/ Mekong river.
-> The Nile is longer than Mekong river
9. English coffee/ bad/ Vietnamese coffee.
-> English coffee is worse than Vietnamese coffee.
10. That mountain/ high/ this one. -> That mountain is higher than this one.
11. He/ run/ fast/ me. -> He runs faster than me.
12. My house/ large/ yours. -> My house is larger than yours
13. She/ work/ hard/ her colleague. -> She works harder than her colleague.
14. This street/ busy/ that one. -> This street is busier than that one.
15. John/smart/ Peter. -> John is smarter than Peter.
16. This shirt/ cheap/ that one. -> This shirt is cheaper than that one.
17. My coputer/ fast/ yours. -> My computer is faster than yours.
18. This road/ narrow/ that one. -> This road is narrower than that one.
19. This room/ bright/ that one. -> This room is brighter than that one.
20. She/ sing/ good/ her sister. -> She sings better than her sister
21. This river/ wide/ that one. -> This river is wider than that one.
22. My mother/ work/ hard/ my father. -> My mother works harder than my father
23. Lan/ swim/ well/ Nga. -> Lan swims better than Nga
24. My sister/ sing/ bad/ my mother. -> My sister sings worse than my mother
25. An ocean/ large/ a sea. -> An ocean is larger than a sea
26. This exercise/ easy/ that exercise.
-> This exercise is easier than that exercise

Ta có: \(E=\frac{F}{q}\)
\(\rArr E=\frac{192.10^{-19}}{1,6.10^{-19}}=120\) (V/m)
D/S: 120 V/m

Ta có: \(I=\frac{q}{t}\)
\(\rArr0,25.10^4=\frac{q}{4.10^{-4}}\)
\(\rArr q=0,25.10^4.4.10^{-4}=1\left(C\right)\)
D/S: 1 C

Từ công thức \(I=\frac{E}{R+r}\) ta có:
\(2=\frac{9}{4+r}\)
\(\rarr8+2r=9\)
\(\rarr2r=1\)
\(\rarr r=\frac12=0,5\)
Vậy điện trở trong của nguồn là 0,5 ôm