1. There are 10 types of energysources. They are: solar energy, wind energy, geothermal energy, hydrogen energy, tidal energy, wave energy, hydroelectric energy, biomass energy, nuclear power, fossil fuels ( coal, oil and natural gas).

2. I can use less electric, use more natural energy,...

3. Renewable energy means the energy never exhausted such as solar energy, wind energy,...

4. I think my carbon footprint is medium.

5. Yes, I have.

1.c: My sister very bad at math, she must do more math exercises.

2.e: I have a stomachache, you shouldn't eat green fruit.

3.f: Nam likes swimming, so does my brother.

4.a: He is gaining wright, he ought to jog every morning.

5.g: What sport do you like best? - Badminton.

6.h: Would you like to play chess? - I'd like but I can't. Have to go now.

7.b: She didn't come there last night. Neither did I.

8.d: Can I go to the movie? - OK. You can go.

Có: A = ( 2 + 2² + 2³ + 2⁴ + 2⁵ ) + ( 2⁶ + 2⁷ + 2⁸ + 2⁹ + 2¹⁰ ) 

còn lại tự lm 

How long does Burning man last?

When does the event begin and ends?

a, My little brother gave me a surprise.

b, Teenagers are not allowed to see this movie.

c, Lance Amstrong is a famous cycler.

d, You don't need to walk so quickly! It's not a completion.

1790

\(\left|\dfrac{-1}{3}-\dfrac{1}{-4}+\dfrac{1}{5}\right|-\dfrac{-1}{2}\\ =\left|\dfrac{-1}{3}+\dfrac{1}{4}+\dfrac{1}{5}\right|+\dfrac{1}{2}\\=\left|\dfrac{-20}{60}+\dfrac{15}{60}+\dfrac{12}{60}\right|+\dfrac{1}{2}\\ =\dfrac{7}{60}+\dfrac{1}{2}\\ =\dfrac{37}{60}\)