1. What is the temperature in Bangkok?
- It is very high./It is low.
2. What is the temperature like in Bangkok?
- It is high./ It is low.
(Which one is right?)
Both are correct.
#1 seems to be asking for a specific number in the answer, such as 10°C.
#2 seems to be asking what the general climate is like. Notice the word "like" in there!
If you simply answer "high" or "low" without any references, I (for one) wouldn't know what you mean. When I lived in the California desert, 100°F on a summer day was low to me, but 114°F was high. Here in Texas, though, 100°F in summer is very high! I think your answers need to be more specific.