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
, 


Answer:
<h2>8.5 g/cm³</h2>
Explanation:
The density of a substance can be found by using the formula

From the question we have

We have the final answer as
<h3>8.5 g/cm³</h3>
Hope this helps you
Answer:
A ability to decompose
B reactivity
Explanation:
Chemical properties are those properties that tell us about what a substance can do as regards to whether or not the substance reacts with other substances.
Examples are flammability, rusting of iron, precipitation, decomposition of water by an electric current.
The ability to decompose and reactivity are chemical properties of a substance.
- Physical properties tells us everything about what a substance is when no change is occurring to its constituents.
- Examples are state of matter, color, odor, taste, texture, hardness e.t.c
Answer:
Those individuals with advantageous traits are more likely to survive and reproduce. The survivors pass down these advantageous traits to their offspring.
Explanation: