Answer:
Kinetic energy to Electrical energy.
Explanation:
When stationary bike is pedaled the wheels of the bike rotates which is a form of kinetic energy, this kinetic energy can be converted into electricity when connected to a generator.
From _Kinetic_ energy to _Electrical_ energy.
Answer:
B) a substance's color and odor changed Explanation: A signal that a chemical change has occurred is when its odor (its smell) or its appearance has changed.
I pretty sure the answer is a
Answer:
1 is the correct answer of the question
Answer:

Explanation:
We can use oxidation numbers to decide which substance is reduced.

The oxidation number of Na changes from 0 in Na to +1 in Na⁺.
The oxidation number of H changes from +1 in H₂O to 0 in H₂.

1 and 4 are wrong because H₂ and Na⁺ are products.
2. is wrong because there is no H⁺ to be oxidized or reduced.