To find angle $ \alpha $ use formula:
$$ \sin \left( \alpha \right) = \dfrac{ h }{ a } $$After substituting $h = 2400\, \text{cm}$ and $a = 600\, \text{cm}$ we have:
$$ \sin \left( \alpha \right) = \dfrac{ 2400\, \text{cm} }{ 600\, \text{cm} } $$ $$ \sin \left( \alpha \right) = 4 $$ $$ \alpha = \arcsin\left( 4 \right) $$$ \arcsin(4) $ is not defined $ \Longrightarrow $ The problem has no solution.