Here each element takes 1 byte ,
Block size=100 Byte each!
each block can hold=100 elements of the array,
So total Number of Block required to hold the entire array is (80x80)/100=64 blocks
Now as given ,the cache capacity is also 64 blocks and "Data Cache is Initially Empty"
Array is accessed twice
For the first access, there will be compulsory misses, we need to bring all of those blocks to cache
so in empty cache,we need to bring 64 blocke ..so there is 64 Misses
for second access, No misses occurs because 64 blocks are already in cache
so overall miss will be 64
More on Misses:http://meseec.ce.rit.edu/eecc551-winter2001/551-1-30-2002.pdf