12-20 please

12. A US social security number is a 3-digit number, a hyphen, a 2-digit number, a hyphen and a 4- digit number. Define a regular expression to match a social security number. 13. Which of the following grep options ignores case so that you would not have to specify both upper and lower case letters in your regular expression? a.c c.I e. There is no such option so you would have to specify both upper and lower case letters if you wanted to match either case 14. We want to replace all instances the string "the Ohio State University" with "THE Ohio State University" from the file degrees.txt. What is wrong with the following sed statement? sed 's/the Ohio State University/ THE Ohio State University' degrees.txt 15. Assume data.txt co nsists of rows of employee information where each employee is denoted by last name, first name, hours worked, hourly wages. Write an awk command to output the last name and hourly wages of all employees who worked exactly 40 hours