Answer:
D) Adding a catalyst
Explanation:
Adding a catalyst decreases activation energy and allows the reaction to occur more easily.
1. <span>Count Sergei Lvovich Levitsky invented the Bellows camera. The correct option among all the options that are given in the question is the last option or option "D".
2. The substance with which the first photograph was made from, was Bitumen. The correct option among all the options given in the question is the first option or option "A".
3. Kodak DCS 100 was the first commercially available digital camera. The correct option among all the options that are given in the question is the first option or option "A".</span>
The iron nail displaces the Cu from the copper sulfate solution. This results in the color of CuSO4's disappearance. Copper is less reactive than iron.
