Refer to the following abbreviated standard reduciton potential table. Which one is the of the following reactions would be considered NON=SPONTANEOUS?
Al^3- + 3e^- aAl -166 V
Zn^2+ + 2e^- a Zn -0.76 V
Pb^2+ + 2e^- a Pb - 0.13 V
2H^+ + 2e^- a Hsub2 0.00 V
Cu^2+ + 2e^- a Cu+0.34 V
Ag+ +e-a Ag+0.80 V
a. 2 Ag^+ + Cu --> 2 Ag + Cu^2+
b. 2 H^+ + Pb --> 2H + Pb^2+
c. 3 Zn^2+ + 2Al --> 3Zn^+ 2Al^3+
d. Hsub2 + Zn^2+ --> Zn + 2H^+