CaF2 + Ca = 1
Li2SO4
CaSO4 +
LiF
-
Ca = 1
F= 2
F = 1
Li = 2
Li = 1
S = 1
S = 2
O = 4
O = 4

Sorry i think the answer is b

Answerelement;

Shoot man tough luck

Firstly, the planetary model of the atom  failed  to explain why individual atoms produce discrete  line spectra. in fact, according to rutherford's model, each individual atom should produce a  continuous  line spectrum. the second flaw to his model was the fact that electrons orbit the nucleus in a circular fashion.