Consider the circuit diagram below. $[$Answer in $2$ significant figures$]$

a$)[12$ pts$]$ What is the equivalent resistance for the sub$-$circuit abcd?

b$)[4$ pts$]$ Redraw the whole circuit with the equivalent resistance found in part a$)$ to replace the sub$-$circuit abcd.

c$)[18$ pts$]$ Using Kirchhoff's Law, find the magnitude and direction of current $($to the left or to the right$)$ through Ammeter A$1$ and A$2.$

d$)[6$ pts$]$ What is the power dissipated by the equivalent resistance found in part a$)?$