For this problem, take $10\backslash$deg C and $1$ atm as the temperature and pressure of clouds. You will need to look up properties for both air and water at these conditions. For each part of the problem, clearly state whether you are assuming flow to be creeping, laminar, or turbulent. After you've found an answer, show whether your assumption was reasonable and re$-$work if necessary.

a$)$ Consider a spherical water droplet that is $10$ micrometers in diameter. What upward velocity of air is needed to keep the droplet suspended? Give your answer in both mm$/$s and mph$.$

b$)$ For a storm of $20$mph updrafts, estimate how big a water droplet in the raincloud must get before it falls. Give your answer in both mm and inches. How does this compare to your intuitions about the size of raindrops?