The length of a rope is 12.072 centimeters. is this number rational or irrational why

Which number produces a rationale number when multiplied by 1/5

Find the volume of the solid whose base is the region bounded by f(x), g(x) and the x-axis on the interval [0, 1], and whose cross-sections perpendicular to the y-axis are squares. your work must show the integral, but you may use your calculator to evaluate it. give 3 decimal places for your answe

What is the perimeter of an isosceles triangle with each leg measuring 2x+3 and the base measuring 6x-2?