What is the balanced oxidation half-reaction from the redox reaction below?

fe + cuso4 --> cu + fe(so4)3

2 fe yields 2 fe2+ + 4e-
2 fe2+ + 6e- yields fe
fe yields 2fe3+ + 6e-
2 fe yields 2fe3+ + 6e-

i need i think its either a or d

Stage in which a typical star has completely stopped fusion

Achemistry student weighs out 0.306 g of citric acid (h3c6h5o7), a triprotic acid, into a 250 ml volumetric flask and dilutes to the mark with distilled water. he plans to titrate the acid with 0.1000 m naoh solution. calculate the volume of naoh solution the student will need to add to reach the final equivalence point. be sure your answer has the correct number of significant digits.

Which of the following is true about a carbonated soft drink? . the carbon dioxide is the solvent, and water is the solute.. the water is the solution, and carbon dioxide is the solvent.. the carbon dioxide is the solution, and the water is the solvent.. the water is the solvent, and the carbon dioxide is the solute.. .