You have performed a serial dilution of an unknown sample and counted 73 cfu on a countable plate that was marked as a 10^-4 dilution and you used a 0-.1 ml to inoculate the plate. what is the population density of the original sample?

Hey there!:

To find the original sample population density, divide the conted colonies by the dilution factor and the inoculate:

= 73 / (10⁻⁴ * 0.1)

= 73*10⁵

Thus, the original sample's population density was 7.3*10⁶ or 73* 10⁵.

Hope this helps!

a rain shadow is a dry region of land on the side that is protected against the prevailing winds of a mountain range. the prevailing winds are the winds that occur most of the time in a particular place of the earth

prevailing winds carry air toward the mountain range. as the air rises up over a mountain range, the air cools, water vapor condenses, and clouds form. on this side of the mountains, called the windward side, precipitation falls in the form of  rain  or snow. this dry air produces a  rain shadow.