Cart Shopping Cart My Store Account Orders Downloads Shopping Cart Remove item Thumbnail image Product Price Quantity Subtotal × Weight Engineering - Winter 2019 $30.00 Weight Engineering - Winter 2019 quantity $30.00 × 30. The Effect of Center of Gravity on Performance $20.00 30. The Effect of Center of Gravity on Performance quantity $20.00 × 14. Weight Predictor $20.00 14. Weight Predictor quantity $20.00 Coupon: Apply coupon Update cart Available coupons (Click to apply). Cart totals Subtotal $70.00 Tax $0.00 Total $70.00 Proceed to checkout