1_ Filter array of strings - only strings starting with 'd' (2 syntax options)

2_ Order array of strings by second and then first characters of each element (2 syntax options)

3_ Select people from IT department (2 syntax options)

4_ Group and list people by department (2 syntax options)

5_ Calculate average age for each department (2 syntax options)

6_ Calculate salary average for department and age (Procedural syntax)

7_ Select distinct names and departments (using grouping)

8_ Select disctinct set (2 syntax options)

9_ First, FirstOrDefault, Single

10_ How to write for each in LINQ

11_ Join Person and Department classes (2 syntax options)

12_ Left outer join for Person and Department classes

13_ Add new person to the List of person or combine 2 lists (3 options)

14_ How SelectMany works

15_ How Zip in works

16_ Calculate factorial. How to seed initial state.

17_ Select object from list based on the object type

18_ Sort list of sss_N{N} strings by N{N} and select N{N} > 2

19_ How to debug LINQ query