SQL ,PLSQL , Unix

Problem Statement Given two tables,  City  and  Country  whose descriptions are given below. Find the sum of population of all the Cities that lies in  "Asia"  continent. City +-------------+----------+ | Field | Type | +-------------+----------+ | ID | int(11) | | Name | char(35) | | CountryCode | char(3) | | District | char(20) | | Population | int(11) | +-------------+----------+ Country +----------------+-------------+ | Field | Type | +----------------+-------------+ | Code | char(3) | | Name | char(52) | | Continent | char(50) | | Region | char(26) | | SurfaceArea | float(10,2) | | IndepYear | smallint(6) | | Population | int(11) | | LifeExpectancy | float(3,1) | | GNP | float(10,2) | | GNPOld | float(10,2) | | LocalName | char(45) | | GovernmentForm | char(45) | | HeadOfState | char(60) | | C...