Answer:
B and D as well
Explanation:
All the electronic configuration of the elements of B end on s sub shell.
S energy level sub shell can hold 2 electrons and since Be, Mg, Ca Sr end in s.
We can say, they have same valence electrons, i.e 2 electrons.
The person above is trying to give you a virus
1. Double replacement (DR)
2. Decomposition (D)
<h3>Further explanation</h3>
1. Al2(SO4)3 + Ca3(PO4)2 -> 2AIPO4 + 3CaSO4
Double replacement (DR) : there is an ion exchange between two ion compounds in the reactant to form two new ion compounds in the product
General form :
AB + CD -> AD + CB
2. 2NaCIO3 → 2NaCl + 3O2
Decomposition (D) : Reactant breakdown into simpler ones(reverse of combination)
General form :
AB ---> A + B