Exercise 1 (8 points): Consider the B+ tree index shown in the figure below. Each intermediate node can hold up to five pointers and four key values. Each leaf can hold up to four records, and leaf nodes are doubly linked as usual, although these links are not shown in the figure. Answer the following questions. Please show every step of the insertion and explain the procesS 30 S0 Il 90 98 I2 30 31 6 6970 79 991001105 LI 5 LS S1521561 60 LA 4 95 96 97 2 L7 42 43 81 82 L6 (1). Insert a record with search key 109 into the tree. (4 points) (2). Delete the record with search key 81 from the original tree. (4 points)