The expression would be $0.20 x f. Once you figure out what the 'f' variable stands for, you have to multiply it by $0.20, and you will have your answer.
Im pretty sure its
A. Number of Organisms
B. Amount of Matter
A million sorrys if im wrong :(
Describe<span> the physical </span>properties of the Sun<span> (sunspot cycles, solar flares, prominences, layers of the </span>Sun<span>, coronal mass ejections, and nuclear reactions) and the impact of the </span>Sun<span> as the main source of external energy for the Earth</span>
Cohesion hold H Bonds together to create surface tension on water. And since water is attracted to other molecules it then sticks to other molecules.
hope i helped
