On average, the size of a rain drop is 0.1-0.5mm. The size of a rain drop depends on the amount of water in an area together. For example, if there are a large number of water drops in a small area and they collide, they would then join together and become a bigger droplet. If they get too big, then then would split into yet another drop.
They vary in size, so you will not find a direct answer
7 miles per hour
they can travel for trillions of miles before raining down on the land
a tiny bit of dust is at the center of every rain drop
WHAT WHAT OMG think it is RAIN RAIN
rain gauge
Bigger than your house.
because
7 miles per hour
if you mean why does rain drop , it is because of gravity
The viscosity of air provides a drag force on a raindrop and keeps it from falling with the acceleration of gravity. When a drop is falling (assuming it does not combine with other drops in the process) it will reach a terminal velocity which depends on its diameter. The larger the diameter the larger the terminal velocity. Specifically, the terminal velocity is proportional to the square root of the diameter of the drop. Big rain drops fall faster than small rain drops. See related links for details and equations.
they can travel for trillions of miles before raining down on the land
In Serbian rain drop is kap kiše
A falling rain drop can hit you up to 18 miles per hour. This is the fastest recorded speed of a rain drop.
a tiny bit of dust is at the center of every rain drop
The nouns are rain and face.
WHAT WHAT OMG think it is RAIN RAIN
rain gauge