All right, we've got a question. Here we have a fuel tank that is an upright cylinder burried so that it's circular top of 10 ft beneath. The ground level tank has released 5 ft and it's 15 ft high. And although the current oil level is on Lee 6 ft deep, we want to calculate the work required to pump all the oil to the surface. The oil weighs £50. Perfect. Cute. Alright, so we'll call the liquid, which is being pumped out out of height. D of h you know the area and be calculated as pi over r squared. Hey, that circular area. And then our volume would be you would just be changed. An area multiplied by the change in height. Excuse me. Area multiplied by the change in heights you have T V is equal to the area multiplied the change. All right, now we can calculate the weight off that layer. Um, excuse me, The liquid is what I'm referring to when I say the layer. So, um, we know that the vault Excuse me? The weight of that would just be the density multiplied by the volume. Alright, that is your weight And so then you could say, Ah, that your like to expand it out its density Excuse me, Rho pi r squared d of h all right. And we can then calculate our, um, work, respect the height, you know, put a dash here, distinguish between weight and work. We have a church one h two and then we plug in our row pi r squared d of H And so our height to we know would be 25 ft because it's already 10 ft underground. And then there's another 15 ft. How high it ISS. And then if we were going to calculate our, um, lower limit, we would take a these 15 as the height and we'll subtracted by, um who told the current oil level is on Lee 6 ft deep. So we'll take the 15 and we will subtracted by our six. And so we'll get nine and then we have nine plus 10. So we'll get 19 as our lower limit the H 1 19. It's too close to 25. And then when you go ahead and salt with this integral, you can pull out the row pie and the r squared. You just have the integral from 19 25 or D of h. So that equals two Rho pi r squared, inch squared. Excuse me. Eight square or two, and that will go from 19 to 25. So you plug in your row density, which we know 50. Hi. And then your radius here would be five were told. Then you have 25 squared over two minus 19. According to you, plug that into your handy dandy calculator, Uh, like plugging into my calculator so you will get 518,000 362.79 pounds. Perfect. Right. And that will be your final answer there. All right, well, I hope that clarifies the question there. Thank you so much for watching.