ocr: 7. A . hot air balloon moves along the curve y-300P1x-2000), starting at the origin. (All measurements are in feet.) When the horizontal distance of the balloon, X, from the origin is 1000 ft., dt dx = 40 ft./min. - How fast is the balloon moving away from an observor at the origin? L 9. a) If the ellipse F+y2-1 - is rotated about the x-axis, what is its volume? b) Set up the integral giving the arc-length of the above ellipse in the first cuadrant. Po not evaluate. a) Without attempting to evaluate constant multipliers, what will be the (algebraical) form of the answer to the integration - 3x ...
