A spring has a spring constant of 800 N/m. How much work must be done to stretch the spring 0.4 m from its unstretched position? A. 64.0 J
B. 160.0 J
C. 320.0 J
D. 640.0 J

Acertain half-reaction has a standard reduction potential e_red^0 = -0.94 v. an engineer proposes using this half-reaction at the cathode of a galvanic cell that e must provide at least 1.00 v of electrical power. the cell will operate under standard conditions. a. is there a minimum standard reduction potential that the half-reaction used at the anode of this cell can have? b. is there a maximum standard reduction potential that the half-reaction used at the anode of this cell can have?