Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_81 ( "Particulars and Characteristics" text, "Shivalik Zone" text, "Mid-Hill Zone" text, "High hill zone" text, "Trance- n Himalaya Zone" text )

### Question ###
For mid-hill zone what is the altitude?

### Accurate SQL ###

SELECT "Mid-Hill Zone" FROM table_81 WHERE "Particulars and Characteristics" = 'Altitude'