Final answer:
The property that is not associated with slow synapse is rapid neurotransmitter release. In a slow synapse, the neurotransmitter release is slower compared to fast synapses.
Step-by-step explanation:
The property that is not associated with slow synapse is 3) Rapid neurotransmitter release.
In a slow synapse, the neurotransmitter release is slower compared to fast synapses.
This slower release leads to a higher synaptic delay, which is the time it takes for the signal to travel across the synapse.
The synaptic strength, or the intensity of the signal, can be high or low in both slow and fast synapses, so it is not a differentiating property between them.
However, the postsynaptic response is slower in a slow synapse, which is the fourth option listed.