a) Suppose you want to verify the integrity of certain files, say system files or softwarepackages downloaded from online. Explain how you can...

a) Suppose you want to verify the integrity of certain files, say system files or softwarepackages downloaded from online. Explain how you can achieve this using MAC andhash functions separately. Also, describe the advantages and disadvantages in usingeach of this technique with respect to the verification of file integrity

b) Can we use a hash function that is not collision resistant to construct a MAC scheme?Justify your answer