Mulan sells liquid detergents to hotels, hospitals, and individual customers through a network of retailers and wholesalers. To reduce environmental impact, the company is considering selling concentrated soap that can be diluted at the place of consumption. Currently the liquid detergents are transported in packs of 10 bottles and each pack weighs 20 pounds. Mulan ships 800 packs per week. Concentrated soap can be shipped in packs of 5 and each pack would weigh 15 pounds. The company expects to ship 100 packs per week. These changes will result in a lighter but more difficult package for shippers to handle. The freight classification has worsened from 65 to 85. Calculate the difference in Mulan's weekly shipping charges.