Kindly verify these and provide answer to others-
$\\\Theta (n).O(n) = ?\\ \Theta (n).\Omega (n) = \Omega (n)\\ O(n).\Omega (n) = \Omega (n)\text{when function is non decreasing and what if it is decreasing?}\\ \Omega (n)+\Theta (n) =\Omega (n)\\ O(n)+\Theta (n) = ?\\ O(n)+\Omega (n)=\Theta (n)$