Radioactive decay is a pseudo-first order reaction. When you know the half-life of the material, you could use this equation.
A= A₀(1/2)^t/h
where
A is the final activity
A₀ is the initial activity
t is the time
h is the half-life
A = (0.64)(1/2)^88/44 = <em>0.16 mbq</em>
The answers are "t<span>ails of comets, the ionosphere, and a neon sign." or options A, D, and E. Tails of comments are mainly made of plasma. Ice cubes are examples of a solid. A gas fire key word gas is example of a gas. The ionosphere is also mainly made of plasma. A neon sign uses plasma in order to work. A flashlight uses a light bulb which isn't a example of plasma therefore thats a no.
Hope this helps!
</span>
Answer:
*Engineers can design better bridges because they know how metal changes shape.
*Scientists can easily classify mixtures of unknown substances.
Explanation:
Tensile strength and the properties of mixtures are physical properties because the substances are not changed into different ones.
A. and C. are wrong. Combustion and other reactions are chemical properties because the substances are changed into different ones
