Need help for the questions below

2-1 The average search time of searching a hash table with N elements is: (2 point(s)) A. O(1) OB. O(logN) OC. O(N) D. cannot be determined 2-2 Which of the following statements about HASH is true? (2 point(s)) A. the expected number of probes for insertions is greater than that for successful searches in linear probing method B. if the table size is prime and the table is at least half empty, a new element can always be inserted with quadratic probing C. insertions are generally quicker than deletions in separate chaining method D. all of the above (2 point(s)) 2-3 Given an initially empty hash table HT with length 7, together with a hash function H(k)=k%7. Let us use linear probing to solve collisions. What is the average search length for successful searches after inserting 22, 43, 15 one by one into HT ? A. 1.5 B. 1.6 O C. 2 O D. 3