Answer:
The answer should be A. Adding carbon to iron makes it tougher and stronger.
We are given the density of mercury which is equal to 13.6 g/ml. Substances which sink in this metal should have densities higher than the density of the metal, otherwise they would float. The substance thta would sink in mercury is C. gold
1 cm = 0.39 inches so we can just 16.2*0.39 and we will get 6.38 inches.
A. the law of conservation of matter only applies to a limited number of chemical and nuclear reactions.