Contact lens solution is salty in order to match your tears

Which strategy is an example of how companies may upgrade themselves to meet changing customer preferences? a.doing door-to-door sellingb.using billboards to advertise the productsc. making online shopping services availabled.giving discounts on products

The influenza virus cause the flu, but not other diseases. why?

What substance is the most acidic. lemon juice. tomato juice. sodium hydroxide. water