  The high precision attained by cosmological data in the last few years has
increased the interest in exact solutions. Analytic expressions for solutions
in the Standard Model are presented here for all combinations of $\Lambda = 0$,
$\Lambda \ne 0$, $\kappa = 0$ and $\kappa \ne 0$, in the presence and absence
of radiation and nonrelativistic matter. The most complete case (here called
the $\Lambda \gamma CDM$ Model) has $\Lambda \ne 0, \kappa \ne 0$, and supposes
the presence of radiation and dust. It exhibits clearly the recent onset of
acceleration. The treatment includes particular models of interest such as the
$\Lambda$CDM Model (which includes the cosmological constant plus cold dark
matter as source constituents).
