As an SC Manager, you are tasked with choosing between two different machines for production. Machine A has a fixed cost of $$2\mathrm{.}5$ million and variable costs of $$10$ per unit. Machine $B$ has a fixed cost of $$4$ million and variable costs of $$6$ per unit. Which of the following is true?

Machine $A$ is best if the number of units expected to be sold is larger than $375,000.$

Machine $B$ is best if the number of units expected to be sold is larger than $375,000.$

Machine A will always produce the lowest total costs regardless of the number of units sold.

Machine $B$ will always produce the lowest total costs regardless of the number of units sold.

None of the above