1. Suppose your database stores 10 data records in the following order where each data block can contain at most 2 data records: [2.5+2.5] (2020-01-11, 1, abc) (2020-01-17, 11, def) (2020-02-29, 4, pqr) (2020-03-05, 12, mno) (2020-03-13, 20, xyz) (2020-03-26, 9, uvw) (2020-04-01, 14, jkl) (2020-04-06, 50, stu) (2020-04-19, 31, vwx) (2020-04-25, 6, ghi) By using this database and data records, design the following index structures, a) Draw a primary sparse index structure where each index record points one data block. b) Draw a secondary dense index structure based on the 3rd column data. Assume each index block can contain at most 4 index records.