An orange grower has discovered a process for producing oranges that requires two inputs. The production function isf(X1,X2)=min{{2x_1,2x₂} where x₁and x₂arethe amounts of inputs 1 and 2 that he uses. The pricesof these two inputs are w₁= $5 and w₂= $1, respectively. The minimum cost of producing 140 units istherefore:

$980.

$700.

$490.

$280.

$630.