Consider the grammar given below:

S → Aa

A → BD

B → b | ε

D → d | ε

Let a, b, d, and $ be indexed as follows:
Compute the FOLLOW set of the non-terminal B and write the index values for the symbols in the FOLLOW set in the descending order. (For example, if the FOLLOW set is {a, b, d, $}, then the answer should be 3210)

Which one of the following kinds of derivation is used by LR parsers?

The value of 3⁵¹ mod 5 is_________.

In an RSA cryptosystem, the value of the public modulus parameter n is 3007. If it is also known that $$\varphi $$(n) = 2880, where $$\varphi $$() denotes Euler's Totient Function, then the prime factor of n which is greater than 50 is ______.