A for number 1 and C for number 2 im sorry i dont know the rest. :3
It would be called an alloy.
To answer this question I would have to know the elements in the compound
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:
b. The number of electrons
Explanation:
A "neutral atom" has a <u>neutral charge</u>. This means that <em>its charge is equal to </em><em>zero. </em>In order for the charges to cancel out each other, the atom's <em>positive charge should be equal to the negative charge. </em>These being said, the number of electrons<em> (negatively-charged)</em> is then equal to the number of protons <em>(positively-charged). </em>Those atoms which are not neutral are called <em>"ions."</em> This means that they either have more or less electrons than the protons.