Acceleration is when something is being moved forward or back, motion is just movement, friction is two or more things rubbing together, so the answer should be B. gravity
Answer:
Element
Explanation:
Because elements can be made with only one atom the rest of the answers cant be
A. soluble.
The are solubility rules that predict precipitation reaction.
Answer:
I believe it would be D, to enhance the survival rate.
Explanation:
Answer:

Explanation:
I am assuming that we have to balance this equation. On the left side, we have one Fe, 2 H, 2 Cl, and 1 S. On the right side, we have 1 Fe, 1 H, 1 Cl, and 1 S. Adding a 2 as a coefficient in front of the HCl on the right side will make 2 H and 2 Cl instead, balancing the overall equation.