Specify the points to which you could connect a voltmeter to measure the following potential differences in Figure 21.47:

(a) The potential difference of the voltage source; 

(b) The potential difference across R₁; 

(c) Across R₂; 

(d) Across R₃; 

(e) Across R₂ and R₃. Note that there may be more than one answer to each part.

= 90 V = r = 0.25 a h b 9 I R = 3.0 [R = 6.0 e R = 1.5