Answer:
4
Explanation:
it will share its valence electrons with other elements to acquire noble gas confriguration of the nearest inert element.
i think A but if I'm wrong sorry
then if increasing then becoming spread out so letter A
Answer:
convection occurs in the inner core and crust
Answer : The half-life of the compound is, 145 years.
Explanation :
First we have to calculate the rate constant.
Expression for rate law for first order kinetics is given by:

where,
k = rate constant = ?
t = time passed by the sample = 60.0 min
a = let initial amount of the reactant = 100 g
a - x = amount left after decay process = 100 - 25 = 75 g
Now put all the given values in above equation, we get


Now we have to calculate the half-life of the compound.



Therefore, the half-life of the compound is, 145 years.