We first write the truth table for required Flip-flop i.e. JK FF

Now we write the excitation table of given FF SR flip-flop as

Now we combine two tables to get the combinational circuit as:

Now we design the combinational circuit to convert J, K to corresponding R, S
K-map for S input:

K-map for R input:

So we get the circuit to convert RS FF to JK FF:
