I know I learned this in school, but when I was on the floor it confused me for some reason. I had a bag of Zosen that was 100ml and it said to infuse over 30 minutes so I set the pump to admin 100ml (RTBI) at a rate of 100. I understand the amt to be infused, but I was told to set the rate at 100? Why 100? What am I missing here? Help please.