Query to Get difference of Hours , Day,Month,Year between two dates

select 24 * (to_date('2016-08-16 22:00', 'YYYY-MM-DD hh24:mi')- to_date('2016-08-17 17:00', 'YYYY-MM-DD hh24:mi') )  'diff hours'
from dual;
     
select (to_date('2016-08-17', 'YYYY-MM-DD')- to_date('2016-08-16', 'YYYY-MM-DD')  )  "Diff Day"
from dual;
 
SELECT MONTHS_BETWEEN (to_date('2016-09-17', 'YYYY-MM-DD') , to_date('2016-08-15', 'YYYY-MM-DD')  ) " diff Months"
 FROM DUAL;
   
SELECT (to_date('2018-09-17', 'YYYY-MM-DD') - to_date('2016-08-15', 'YYYY-MM-DD')) / 365.242199  "Diff Year"
FROM dual