Answer:
3/4 of the storage capacity are wasted.
the wastage for a real file system will be lower
Explanation:
If the file size is 1 kb and the file system uses 4-kb disk blocks, then 4 - 1 = 3 kb are being wasted. That represents 3/4 of the storage capacity.
I think the wastage for a real file system will be lower because every file system has disk blocks with different capacities and they are used considering the file size, using the storage capacity efficiently.