How are nerve impulses transmitted across a synapse?

True about electrical synapses:
$(I)$. Pre and postsynaptic neurons are in very close proximity.
$(II)$. Pre and postsynaptic neurons are separated by a synaptic cleft.
$(III)$. Impulse transmission is very fast.
$(IV)$. Electrical synapses are common in our system.
Select the correct option.

How long does the synaptic delay last (in $, ms$)?

The brief delay in the transmission of an impulse through a synapse is called .........

$A$ : Transmission of the nerve impulse across a synapse is accomplished by neurotransmitters.
$R$ : Transmission across a synapse usually requires neurotransmitters because there is a small space,$i.e.$,synaptic cleft,that separates one neuron from another.

The receptors of neurotransmitters are present on/in the