Water moved through the water cycle by changing its state. Think, for example, of water evaporating (liquid to gas), snow sublimating (solid to gas) or melting (solid to liquid), rain (gas to liquid), sleet (liquid to solid), or snow (gas to solid).
The answer would thus be A.
The equilibrium constant expression for KSP of Sr3(PO4)2 is
KSP={(Sr^2+)^3 (PO4^3-)^2/ Sr3(PO4)2}
Explanation
write the ionic equation for Sr3(PO4)2
Sr3(PO4)2 → 3Sr^2+ + 2 PO4^3-
KSP is given by (concentration of the products raised to their coefficient /concentration of reactants raised to their coefficient)
Atomic mass Calcium ( Ca) = 40.078 u.m.a
40.078 g --------------- 6.02x10²³ atoms
187 g ------------------- ??
187 x ( 6.02x10²³) / 40.078 =
1.125x10²⁶ / 40.078 = 2.808x10²⁴ atoms
hope this helps!