A section of an electrolyte solution is contained in a vertical tube. During a brief interval:
• Na+ ions move upward, transferring charge at a rate of 2mC/s.
• Cl− ions move downward, also transferring charge at 2mC/s.
• Electrons injected from a wire drift downward through the solution at 1mC/s.
What is the direction of the net conventional current in the tube during this interval?
a) Downward
b) Upward
c) There is no net conventional current
d) Horizontally toward the east