Hit ratio of the cache memory read request is 85% and the cache memory is 5 times faster than main memory. Block size in memory organization is 4 words. The access time of the main memory is 72 ns per word. Write through protocol (simultaneous memory organization) is used in the system. CPU generates 60% of the read requests to read the data and the remaining for write operation. What is the average access time (in ns) of the memory when considering both read and write operations?