 for the first problem we're going to see what happens if we completely eliminate our use of oil and so to do to do this problem first we just run the control version so we hit run and it says those results that's with all the switches in the off position now we're going to turn the oil switch on we're going to turn f oil new to zero that means oil after the adjustment will represent zero of our energy so that completely eliminates it and remember the renewable fraction will rise as a result of that we have to make sure the start time is a 2020 the adjust time is a 2 we don't change the per capita energy or the population and we run the model again now and we see different result here now I'm going to look at page two this shows the total emissions this is what we're interested in we want to find the total emissions in 2100 and how they differ so I slide the cursor along back and forth here until I get to 2100 that's right in there and I see that in run one that's our control it was 29.57 gigatons of carbon emitted and then in run two it's down to 19.78 and so it's a difference of 9.79 and that's the answer that we're looking for that difference the reduction basically the distance between the blue curve and this dotted red one here