Answer from cs61c-ew (Joo-Rak Son 16103505) for Question 1
Supposing that we do not use any offset, 
53 mod 8 = 5 is the index, which occupies right 3 bits.
53 - 5 = 48 is the tag, which occupies rest of the bits (29 bits).
In binary, the tag would be,
0000 0000 0000 0000 0000 0001 1000 0