Make me a chart based on Spreadsheet data

A chart showing the simultaneous build up and elimination from the body of an insufflated toxin over a period of time. For example a toxin is ingested during varying intervals (lets say 15 minutes in this example) which then takes a fixed period of time to eliminate to half strength (lets say 1 hour in this example). So every 15 minutes the toxin level will increase by the amount taken and start to taper off at a constant rate towards half strength, but during that time and the next few hours, additional toxins will be ingested so the levels are cumulatively building up in the body at a faster rate than being eliminated. The sample will involve approximately 20 ingestion data points of the toxin and associated elimination tapering off periods over a time frame of around 12 hours. Basically I'm trying to show the accumulated effect of toxin build up when taken faster than rate of elimination from full strength to half strength. I can make a simple chart myself based on data points. But why I'm offering a payment to have this done is that I don't know how to make a professional looking chart with lines that show the tapering off effect from my data points, basically showing every data point constantly tapering from full to half value every 60 minutes whilst also being boosted at every intermittent data point. I suck at maths! Looking forward to some assistance with this initial mini project. Much more to follow. Best. Colin.