A company developed the following per-unit standards for its product: 5 kilograms of direct materials at $3.20 per kilogram. Last month, 1000 kilograms of direct materials were purchased for $2880. Also last month, 650 kilograms of direct materials were used to produce 133 units. What was the direct materials price variance for last month?

$13760 favourable

$320 favourable

$13760 unfavourable

$320 unfavourable