Read the given statements and select the correct ones.
(i)Autonomic neural system transmits impulses from the CNS to the voluntary organs and striated muscles of the body.
(ii)Unmyelinated nerve fibres do not have Schwann cells which form the myelin sheath.
(iii)Axonal membrane of a neuron while not conducting any impulse is comparatively more permeable to potassium ions `(K^+)` than to sodium ions `(Na^+)`
(iv)A synapse is formed by the membranes of presynaptic neuron and a post synaptic neuron.