Conditioned stimulus
Classical conditioning is a learning procedure in which a biologically potent stimulus paired with previously neutral stimulus. This pairing will cause a response that can be the same as the potent stimulus. This is done repeatedly for an organism to elicit a conditioned response to the previously neutral stimulus that was paired to the active stimulus. The dog salivates due to the idea that food is related to the sound of the bell.
The iron-nickel alloy melts cause of the hot temperatures
I believe the answer is tertiary
When a nerve impulse reaches the end of an axon, the axon terminal released ACh into the synaptic cleft. 2. ACh diffuses across the cleft and attaches to the ACh receptors on the sarcolemma of the muscle fiber. 3. ACh binding triggers electrical events that ultimately generate an action potential.
Because they are in different galaxies. I hope this helps! :)