According to the graph, how long is the half life of the original substance? *

It is around 2.75 units of time.

Explanation:

Half life defines the time that a quantity of a sustance reduces to it's half.

So if we initially have a mass A of a given substance, after the half life time, we will have a mass of A/2.

In our graph we can see that at time t = 0, we have 100000 atoms, the half life time will be the time at witch we have 100000/2 = 50000 atoms.

You can see that this happens at something between 2.5 and 3 units of time.

If you llok at the time t = 6, we have 30000 atoms, so now we need to see at what time the number of atoms is around 15000 atoms.

this happens at time betwen 8.5 and 9

and 8.5 - 6 = 2.5

9 - 6 = 3

So the half time of the substance is between 2.5 and 3 units of time, we can select the average and say that the half life time is 2.75 units of time

this is math not biology xd

do yall know the answer?