Chapter 9 - Querying and Manipulating Data with LINQ

1. What are the two required parts of LINQ?
   • A LINQ provider and the LINQ extension methods. You must import the System.Linq namespace to make the LINQ extension methods available and reference a LINQ provider assembly for the type of data that you want to work with.
2. Which LINQ extension method would you use to return a subset of properties from a type?
   • The Select method allows projection (selection) of properties.
3. Which LINQ extension method would you use to filter a sequence?
   • The Where method allows filtering by supplying a delegate (or lambda expression) that returns a Boolean to indicate whether the value should be included in the results.
   • List five LINQ extension methods that perform aggregation.
   • Max, Min, Count, Average, Sum, and Aggregate.
4. What is the difference between the Select and SelectMany extension methods?
   • Select returns exactly what you specify to return. SelectMany checks that the items you have selected are themselves IEnumerable...