Linked Lists
Question 1 
O(log^{2} N)  
O(N)  
O(N^{2})  
Θ(N^{2} logN) 
Question 1 Explanation:
In Doubly linked list (sorted)
→ Delete needs O(1) time
→ Insert takes O(N) time
→ Find takes O(N) time → Decrease by takes O(N) time
Now number of each operation performed is given, so finally total complexity,
→ Delete = O(1) × O(N) = O(N)
→ Find = O(N) × O(log N) = O(N log N)
→ Insert = O(N) × O(log N) = O(N log N)
→ Decrease key = O(N) × O(N) = O(N^{2})
So, overall time complexity is, O(N^{2}).
→ Delete needs O(1) time
→ Insert takes O(N) time
→ Find takes O(N) time → Decrease by takes O(N) time
Now number of each operation performed is given, so finally total complexity,
→ Delete = O(1) × O(N) = O(N)
→ Find = O(N) × O(log N) = O(N log N)
→ Insert = O(N) × O(log N) = O(N log N)
→ Decrease key = O(N) × O(N) = O(N^{2})
So, overall time complexity is, O(N^{2}).
Question 2 
Let P be a singly linked list. Let Q be the pointer to an intermediate node x in the list. What is the worstcase time complexity of the best known algorithm to delete the node x from the list?
O(n)  
O(log^{2} n)  
O(logn)  
O(1) 
Question 2 Explanation:
Worst case complexity for deleting a node from singly linked list is O(1).
Question 3 
Linked lists are not suitable data structures of which one of the following problems?
Insertion sort  
Binary search  
Radix sort  
Polynomial manipulation

Question 3 Explanation:
In linked list finding an element take O(n) which is not suitable for the binary search. And time complexity of binary search is O(log n).
There are 3 questions to complete.