Alpha Enterprise sells ceramic vases for $$321$ each. The direct materials cost per unit is $$155$and the direct labour is$2\mathrm{.}3$ hours per unit at a rate of $$28$ per hour. Manufacturing fixed overhead is applied on the basis of labour hours at a rate of $$42$ per hour. Alpha makes and sells$1021$units per period.

Compute the number of units Alpha Enterprise must sell to breakeven.