Need a fast order form that has product weight and total weight columns

[ThomasHubSpoke]

Currently we are using the Wholesale Order Form & ReOrder app which gives this-

The layout is what we want, but we need another column that will show total weight e.g if a product weighs 2kg the and you set the quantity to 2 then the total weight will show as 4kg. 

Does anyone know how we can achieve this.