Identify the water transport pathways $P$ and $Q$ shown in the given figure.

Consider the following statements and choose the correct answer:
$I.$ Carrier proteins are needed by both facilitated diffusion and active transport and are sensitive to inhibitors that react with protein side chains.
$II.$ Different types of proteins present in the membrane play a major role in both active as well as passive transport.
$III.$ The carrier proteins needed by facilitated and active transport are specific.
$IV.$ There is no need of energy to pump molecules against a concentration gradient in active transport.
$V.$ Transport rate reaches a saturation point when all the active proteins are used.

$A$: Simple diffusion is a passive transport process.
$R$: Passive transport does not require energy.

In which type of transport is the mediation of carrier molecules specifically required?

What are the factors affecting the rate of diffusion?

In which movement, transport molecules are necessary but energy is not utilized?