Sugar cube is my answer
Hope this helps!
Let me know if i'm wrong.
Given, half life of a certain radioactive element = 800 years.
Amount of substance remaining at time t = 12.5%
Lets consider the initial amount of the radioactive substance = 100%
Using the half life equation:
A = A₀(1/2)^t/t₁/₂
where A₀ is the amount of radioactive substance at time zero and A is the amount of radioactive substance at time t, and t₁/₂ is the half-life of the radioactive substance.
Plugging the given data into the half life equation we have,
12.5 = 100 . (1/2)^t/800
12.5/100 = (1/2)^t/800
0.125 = (0.5)^t/800
(0.5)^3 = (0.5)^t/800
3 = t/800
t = 2400 years
Thus the object is 2400 years old.
We have that the the density of FeS is mathematically given as
From the question we are told
Iron(II) sulfide has a primitive <em>cubic</em> unit cell with <em>sulfide</em> ions at the <em>lattice points.</em>
The ionic radii of iron(II) ions and sulfide ions are 88 pm and 184 pm, respectively.
What is the density of FeS (in g/cm3)?
<h3>
Density</h3>
Generally the equation for the Velocity is mathematically given as

For more information on ionic radii visit
brainly.com/question/13981855
Explanation:
is b or c but i think asnwer is b