Here's my solution to this practice activity.
Question 1
select [name] + 'A' from sys.all_columns
Question 2
select [name] + N'Ⱥ' from sys.all_columns
Question 3
select substring([name],2,len([name])-1) as [name] from sys.all_columns
Question 4
select substring([name],1,len([name])-1) as [name] from sys.all_columns