Which function returns a valid value without any

The correct options are Today and Now, as they do not require any arguments. Today's function returns the date of the current day. And the Now function requires no argument as well. and it returns the current date and time of the system. And all the other options take an argument. And hence the correct option is Today and Now.

Explanation:

The options are:

TODAY

SQRT

COUNT

ROUND

NOW

And the answer is as mentioned in the answer section.

these  signals travel  down a part of the neuron called the axon, which is like a wire that carries the  signal  to othernerve  cells. on average a  nerve  cell sends a  signal  at about 50 meters per second, which is over 100  miles  an hour!