Suppose that a small mainland tortoise and a large island tortoise are placed in the same pen at a zoo. which tortoise will experience greater variation in body temperature over a 24 hr period, the small or large tortoise?

Both small mainland tortoise and large island tortoise placed in same pen at zoo will not experience any greater variation in body temperature over a 24 hr period.  

Explanation:

It is because they are ambient in nature which means that their body temperature remains unchanged with responds to the environment. At 13℃ the tortoise are inactive and during this temperature any variation is not seen in the body temperature of the tortoise and it is same for both big as well as small tortoise.

option a is correct i.e.

explanation:

in context to the membrane of nerve impulse, the outer membrane of neuron is semi permeable that is only sodium ions can pass through the membrane i.e. smaller ions can pass through the membrane while larger ions cannot pass through it.

d is the answer

sorry if its wrong!