Answer: b} The exact time when an individual atom will decay can be accurately predicted.
c} After each half-life, the amount of radioactive material is reduced by half.
Explanation:
All radioactive decay follows first order kinetics.
Rate law expression for first order kinetics is given by:
where,
k = rate constant
t = time taken for decay process
a = initial amount of the reactant
a - x = amount left after decay process
Expression for calculating half life, which is the time taken by the half of the reactants to decompose is:

Copper Sulfate (CuSO4) compound is basically comprised of Copper (II) ion and Sulfate ion. Ions are C<span>u2</span>+ and S<span>O4 2</span><span>−</span>.
<em>ANSWER:</em><em>Cu 2+ and SO4 2-</em>