Motor Cross Ltd's Inventory Purchases for the Month of January

Multiple Choice

Motor Cross Ltd's inventory purchases for the month of January are summarised below.Using the weighted-average method of valuing inventory,the weighted unit cost is:
$\begin{array}{lcc}\text{Purchase date}&\text{ Number of units}&\text{ Cost per unit}\\\\\text { 2. January } & 8 & \$ 5000 \\ \text { 13 January } & 12 & \$ 8500 \\ \text { 17 January } & 35 & \$ 7000 \\ \text { 27 January } & 20 & \$ 10500\end{array}$

A) $10 500
B) $ 7 960
C) $ 7 750
D) $ 8 500