Bjorni Inc. makes a single product the Bjorn. Information for 2010 appears belo

Bjorni Inc. makes a single product the Bjorn. Information for 2010 appears below:
Sales in units- 200000

Production in units- 250000

Beginning inventory- 0

Variable production cost per unit- $1.00

Variable selling cost per unit- $0.30

Fixed production cost per year- $100000

Fixed selling and administrative cost per year- $50000

Selling price per unit- $3.00

How much is the cost per unit of inventory using variable costing?

a) $1.00

b) $1.30

c) $1.40

d) $1.70

(Please explain to me how you came up with the answer)