Questions

Passivity of iron is due to formation of an extremely thin and impervious film of ferrosoferric oxide Fe3O4on the surface of iron. Chromic acid, being a powerful oxidising agent (like nitric acid ) renders iron passive. 

Answer: J

Explanation:   Start with the letter J in the top left square, and move clockwise around the other squares. Letters follow the alphabetic sequence, skipping 4 letters at a time. Start with the X in the inner square in the top left, and move clockwise. These inner letters also follow the alphabetic sequence, skipping 5 letters at a time

When traveling in a vacuum, electronic waves from the electromagnetic spectrum all travel at the same speed. Velocity is speed with direction, so they would all travel at the same velocity, realtively speaking. But frequency and wavelength are quite different.

Answer D is correct because a sunk cost is a project expense that will eventualy need to be paid. Answer A is incorrect because a fixed cost remains constant, regardless of any change in a company's activity. Answer B is incorrect because direct cost can be directly linked to producing specific goods or services. Answer C is incorrect because a variable cost changes in proportion to a change in the company's activity or business.