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Surface by rotating the arc y^2=9x from x=0 to 4 through 2π around x axis is 49π.Show that
x̄ of this surface is: 3/49*integral{x(4x+9)dx}? How ruler describe me? Prove that the product of two consecutive multiples of 5 is always an even number? What is the mass of nitric acid that can be produced from 549g of ammonia? Please include steps so I can learn to do it on my own, thanks!? When given the equations x-y=-1, 2y-x=27, x+y =11 how would you use row echelon form to get to the answer (5,6)?