Can you explain please why here answer is 3,960 ? Thank you

Hefty Company wants to know the effect of different inventory methods on financial statements. Given below is information about beginning inventory and purchases for the current year. Sales during the year were 2, 700 units at $5.00. If Hefty used the first-in, first-out method, ending inventory would be: a. $2, 780 b. $3, 960 c. $9, 700 d. $10, 880 Hefty Company wants to know the effect of different inventory methods on financial statements. Given below is information about beginning inventory and purchases for the current year