Hormones ! hope i helped :)
Answer: half life
Explanation: Radioactive decay follows first order kinetics and the time required for the decay of a radioactive material is calculated as follows:

t= time required
k= disintegration constant
x= amount of substance left after time t
a= initial amount of substance
when one half of the sample is decayed, one half of the sample remains and t can be represented as 
at
, 


Thank you for posting your question here brainly. Based on the problem mentioned above the largest mass that water molecule could have using other isotopes is <span>24 amu. Below is the solution, I hope the answers helps.
</span><span>T2_18O = 24</span>
Velocity is explained as the *speed and *direction something might move. Speed means moving and Direction means a certain way (not stationary.)
Hope this helps!
Answer: There are 0.000043 moles of melatonin.
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number
of particles.
To calculate the moles, we use the equation:

given mass = 10 mg = 0.01 g
molar mass of
= 232.28 g
Thus there are 0.000043 moles of melatonin