1, I stayed up late to complete my homework despite being tired.

2,Staying in a hotel is  more comfortable than camping. 

3,My son used to read comic books every night. 

4,You are not allowed to take photos in the museum. 

1,A local festival is different from an international festival in its scale.

2,The next semester starts on 5th January. 

3,Although the bus was late, I still arrived at school on time yesterday.

1. Schools typically have breaks during the summer and Tet holiday.

2. People will use self-driving cars to travel around cities more easily.

3. You must show your passport at the airport security check.

1,The film was a success despite having a low budget. 

2,You mustn’t throw trash out of your car window in traffic.

3,The food at that stall was more delicious than the food at this one. 

4,There are not enough notebooks for the students. 

1,I think we will travel by hyperloop in the future. 

2,Traffic in big cities is often worse than in small towns.

3,Are there usually special activities for children at festivals?

1. Motorbike taxis, called "xe om," are popular for short trips

2. People can watch films on streaming services like Netflix.

3. Waterfalls and rivers are natural sources of hydropower

1,The film was a success despite having a low budget. 

2,You mustn’t throw trash out of your car window in traffic. 

3,The food at that stall was more delicious than the food at this one. 

4,There are not enough notebooks for the students . 

1, I think we will travel by hyperloop in the future. 

2,Traffic in big cities is often worse than in small towns.

3,Are there usually special activities for children at festival?

1. Motorbike taxis, called "xe om," are popular for short trips.

2. People can watch films on streaming services like Netflix.

3. Waterfalls and rivers are natural sources of hydropower.

Ta có zOy^=xOy^+yOz^=4⋅yOz^+yOz^=5⋅yOz^zOy​=xOy​+yOz​=4⋅yOz​+yOz​=5⋅yOz​ (1).

Mà yOt^=90∘⇔90∘=yOz^+zOt^=yOz^+12xOz^=3.yOz^⇔yOz^=30∘yOt​=90∘⇔90∘=yOz​+zOt=yOz​+21​xOz=3.yOz​⇔yOz​=30∘ (2) .

Thay (2) vào (1), ta được: xOz=5.30∘=150∘xOz=5.30∘=150∘.

Vậy xOy^=150∘xOy​=150∘.