Using Newtons Second Law:
F = m×a
F = (0.25 kg)(-2 m/s²)
F = -0.5 N
<h2>The correct option is C</h2>
We use the radioactive decay equation for this problem which is expressed as:
An = Aoe^-kt
An is the remaining amount after time t, Ao is the initial amount and k is a constant.
First, we determine the k from the half life as follows:
An/Ao = 1/2 = e^-k(14.4)
k = 0.04814
Then, we can calculate An after 28.8 yr.
An = 1000 e^-0.04814(28.8)
An = 250 g
