2. Collision avoidance (9 pts) a) (3 pts) One problem with linear probing is "primary clustering." Please explain what this problem is. (3 pts) Quadratic probing was proposed to overcome the disadvantage of primary clustering. However, it may create a new problem called "secondary clustering." Please explain what this problem is b) c) (3 pts) In double hashing, if we choose the second hash function hash2(x) R (x mod R) to resolve the collision, why we would like to make R a prime number