Part 1 Multiple choice (22 points in total, 2 points for each): Note: each question may contain one or more correct answers. 1) Which of the following command(s) can be used to check if the string "aabbcc" matches a pattern described by regex "aa.*" or not? (a) expr "aabbcc" : "aa.*" (b) echo "aabbcc" | egrep 'aa.*" (c) expr match "aabbcc" 'aa.*' (d) egrep 'aa.*' (b) #include (c) #include stdio.h (d) include stdio.h 3) Ifc is a variable of type char and i is a variable of int type, which one of the following statement is illegal? (a) c=165'; (c) c-putcharO; (d) getchar(c)