Answer:
The answer to your question is letter B.
Step-by-step explanation:
The correct answer is letter B because both Copper and Iron as reactants have an oxidation number of zero and when they have reacted their oxidation numbers would be different from those.
A redox reaction is a reaction that involves a transfer of electrons from one atom to another and the oxidation numbers of the reactants are different from the oxidation numbers from the products.

if you have already covered slopes, you could also get it that way, in fact is simpler that way.
Answer:
initial velocity = 64 m/s
Step-by-step explanation:
Differentiate H = 64t - 16t² to find an equation for velocity:
Velocity =
= 64 - 32t
Initial velocity (u) is when t = 0:
u = 64 - 32(0)
⇒ u = 64 - 0
⇒ u = 64 m/s