Question: write relational algebra queries this Question : 10 Consider the following schema. Express the following queries in Relatio Jump to Country (Name, continent, population, GDP,

write relational algebra queries this Question : 10 Consider the following

write relational algebra queries

this Question : 10 Consider the following schema. Express the following queries in Relatio Jump to Country (Name, continent, population, GDP, life-expectancy) River (Name, origin, length) City (Name, country, population) GDP and population in million a) Find all countries where life expectancy is greater than 70 years [2] b) Find the longest river [2] c) List all cities of which are not in Asia [3] :) List the population of countries that have river originating in them [3]

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