Answer:
Internal fragmentation occurs when the last allocation unit is not full. External fragmentation occurs when space is wasted between two allocation units. In a paging system, the wasted space in the last page is lost to internal fragmentation.
In a paging system where fixed size of pages are allocated to the program and last partition of the program may not require entire page.
In a pure segmentation system where memory is not contiguously allocated in fixed partition leading to unused memory blocks.
Step-by-step explanation: