Pat pours cold, liquid cream into a cup of hot coffee. which of the following describes how the hot coffee and cold cream will interact?
a) the cold cream will drop to the bottom of the cup. when it warms, some of it will rise back to the surface.
b) the cold cream will drop to the bottom of the cup. it will remain there, unless it is stirred.
c) the cold cream will remain at the surface. when it warms, some of it will fall to the bottom of the cup.
d) the cold cream will immediately reach the same temperature as the coffee and spread evenly though the cup.

A) The cold cream will drop to the bottom of the cup. When it warms, some of it will rise back to the surface.

Because:

Convection is what drives the spread of the cold cream through the hot coffee. Since the cold cream is denser than the hot coffee, it will drop to the bottom of the cup. The cream's density will decrease as it warms. Once the cream at the bottom warms past a certain point, its density will be low enough that some of it will rise back to the surface.

a saline water is fed to a reverse osmosis unit at flow rate o rotameter connected to reject (retentate) line reads 8 installed in reject and permeate line reads 15.2 milli siemens/cm and 300 micro siemens/com respectively.