Yea this question is difficult for me ive been trying to answer this for 40 mins

it is difficult

my best answer would be a. 6

hope its right!!

Explanation:

The half-life formula is

y = A*(1/2)^(x/H)

where A is the starting amount, H is the half-life, x is the time value and y is the amount after x units of time have passed.

I'll express the x and H values in terms of millions of years. So for example, when we say H = 500, then that really refers to 500 million years.

In this case, we know that,

Let's use those values to solve for x. We'll need logs to cut the exponents down from the trees.

y = A*(1/2)^(x/H)

3 = 192*(1/2)^(x/500)

3/192 = (0.5)^(x/500)

0.015625 = (0.5)^(x/500)

log(0.015625) = log( (0.5)^(x/500) )

log(0.015625) = (x/500)*log(0.5)

(x/500)*log(0.5) = log(0.015625)

x = 500*log(0.015625)/log(0.5)

x = 3,000

Keep in mind that x is in millions of years. So saying x = 3,000 means 3,000 million years. This translates to 3,000*10^6 = 3,000,000,000 = 3 billion years.

It will take about 3 billion years for the 192 atoms to decay to only 3 atoms.

The amount of half-lives this occurs is x/H = (3,000)/500 = 6

So the time span of 3 billion years is the same as 6 half-lives when each half-life is 500 million years long.

bacteria that live on the ocean floor are sustained by phytoplankton. phytoplankton, microscopic marine photosynthetic organisms, have a vastly significant role to play not only in the marine food web of which they’re part of, but also on a more global scale. despite their infinitely small size in comparison to other marine organisms, these tiny creatures occupy an immensely important ecological niche: they are the foundation of the marine food web, and as primary producers, play key roles in supporting all other organisms in the marine environment, as well as in the regulation of the earth’s climate through the sequestration of carbon, oxygen production, and other related processes. phytoplankton account for roughly half of all global primary productivity; therefore, their significance extends far beyond the marine environment alone. there is an intriguing sense of irony in the realization that these tiny living beings that often live out their existence unnoticed and undetected by the rest of the world, have such a far-reaching impact on the lives of virtually all other living organisms on the planet, particularly on those in the marine environment. the world that we have become accustomed to has been and is continuously shaped by the workings of these miniscule yet vital “plants of the sea”.

hope this !

u

explanation: