This is 1 question so don't say chegg rules or whatever please it's a 1 question

V. The EXT3 file system of Linux uses a multiple index structure. If the file i node (inode) contains 15 pointers(or address entries) noted as addr[0]~addr[14]. Assuming that the block size is 4KB and size of a pointer is 4B,

Please briefly explain the specific meaning of these address entries and the advantages of multi-Level indexed files structure.

If the initial length of file A is 25KB, how many pointers in i-node will be accessed when the contents of A is accessed ? Please explain the reason.

Later, if length of A keeps increasing,and its length becomes 6MB, how many address pointers in the i-node need to be accessed when the contents of A is accessed? What if it reaches 6G? Please explain the reason.