A certain computer system was designed with cache memory of size $1$ Kbytes and main memory size of $256$ Kbytes. The cache implementation was fully associative cache with $4$ bytes per block. The CPU memory data path was $16$ bits and the memory was $2-$way interleaved. Each memory read request presents two $16-$bit words. A program with the model shown below (Fig.5) was run to evaluate the cache design.

Answer the following questions:
- What is the hit ratio?
- Suggest a change in the program size of model to improve the hit ratio significantly.