At what temperature range can mercury be found as a liquid

375°

Explanation:

it is because the boiling point of mercury is 375°

Mercury’s melting point (also known as freezing point) is -38.83 degrees Celsius, or -37.89 degrees Fahrenheit. Anything lower than this will cause Mercury to freeze into a solid. If heated above this, it will become liquid.
Mercury’s boiling point is 356.73 degrees Celsius, or 674.11 degrees Fahrenheit. Anything above this will cause Mercury to boil. Below this will cause the Mercury to become liquid.
So, in Celsius, the temperature that Mercury can be found as liquid is -38.83 - 356.73 degrees. Or, a total of 395.56 degrees.
In Fahrenheit, the temperature that Mercury can be found as liquid is -37.89 - 674.11 degrees. Or, a total of 712 degrees.

The ground(Earth's surface) is at low potential whereas the clouds are at higher potential. Due to this potential difference, we see lightning.