Solve the Standard Minimization Problem Using Duality $c = 0.5 s + 0.1 t$

Short Answer

Solve the standard minimization problem using duality.
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Minimize $c = 0.5 s + 0.1 t$ ​
subject to $$\begin{array} { l } 30 s + 20 t \geq 600 \\0.1 s + 0.4 t \geq 4 \\0.2 s + 0.3 \geq 4.5 \\s \geq 0 , t \geq 0\end{array}$$ ​ $c =$ __________
​ $s =$ __________
​ $t =$ __________