<span>noun1.an act or instance of nullifying.2.the state of being nullified.3.(often initial capital letter) the failure or refusal of a U.S. state to aid in enforcement of federal laws within its limits, especially on Constitutional grounds.</span>
The time it takes for 1g of strontium-90 to decay to 250 mg is; 57.6 years
<h3>What is the half life of an element?</h3>
The formula for half life is;
A(t) = A₀ * (¹/₂)^(t/t_1/2)
Where;
A(t) is amount left after t years
A₀ the initial quantity of the substance that will undergo decay;
t_1/2 is the half-life of the decaying quantity.
We are given;
t_1/2 = 28.8 years
A₀ = 1 g
A(t) = 250 mg = 0.25 g
Thus;
0.25 = 1 * (¹/₂)^(t/28.8)
log 0.25 = (t/28.8) log (1/2)
-0.60206 = (t/28.8) * -0.3010
t = 2 * 28.8
t = 57.6 years
Read more about half life at; brainly.com/question/11152793
Answer:
The correct answer is letter "B": The wire brush can remove too much material from the posts of the battery.
Explanation:
While cleaning a battery there are several considerations to be taken in order not to damage its function. At the moment of cleaning the posts, we must be very careful since this is the principal contact with the vehicle cables. In front of any damage, the vehicle may not even start.
Thus, using a soft wire brush with an electric drill is not appropriate since it could remove more material than the necessary from the posts.
What are the the colleges they listed?
Bringing in money, paying bills, housing, etc