In the formula Depth= V(T/2), why is the T (time) divided by 2?

The time taken is 2x the depth of the sea

Linear motion consists of 2: constant velocity motion with constant velocity and uniformly accelerated motion with constant acceleration  

An equation of constant velocity motion  

x = distance = m  

v = speed = m / s  

t = time = seconds  

The principle used in measuring depth is to use the reflection of sound waves emitted by the instrument towards the bottom of the sea. The sound will be reflected and received back by the instrument. So that the time taken is 2x the depth of the sea (emitted time + reflected time), so that the calculation of the depth distance must be divided by 2

colorless gas, exhibiting a blue glow when placed in an electric field

b) solid

its a type of rock

you need to have a picture of the atom that way we can answer it