S1: FALSE.
A ∩ B can be empty which is finite. E.g.,
A=[-1,0] (set of all real numbers between -1 and 0) and
B= N, the set of natural numbers.
S2: FALSE
Given A ⊆ B, the we can assume that B= a^xb^yc^z where x,y,z are non-negative integers(which is Regular). Now assume another language A = a^nb^nc^n; n belongs to non-negative integer(which is CSL).
Clearly all the strings which follows A will be in the subset of strings generated by B. But we cannot make strings in A to be accepted by finite automata ,so A is not reducible to B. If it would be possible then surely FA would be enough to accept any CSL which is not correct...