A mould has a down sprue whose length is 20 cm and the cross-sectional area at the base of the down sprue is 1 cm2. The down sprue feeds a horizontal runner leading into the mould cavity of volume 2000 cc. The time required to fill the mould cavity will be

• A. 10.1 s
• B. 4.05 s
• C. 5.05 s
• D. 7.25 s