A teacher is interested in students’ opinions about an upcoming school dance. Which of the following techniques uses systematic random sampling? Survey the first 10 students who arrive.
Survey every 10th classroom as the teacher walks down the hallway.
Survey the 10th student arriving at school (with the number 10 being randomly chosen), then survey every 12th student after that.
Survey the 10th student arriving at school (with the number 10 being randomly chosen), then survey every other boy and every other girl after that.

To find the extreme values of a function f(x.y) on a curve x-x(t), y y(t), treat f as a function of the single variable t and use the chain rule to find where df/dt is zero. in any other single-variable case, the extreme values of f are then found among the values at the critical points (points where df/dt is zero or fails to exist), and endpoints of the parameter domain. find the absolute maximum and minimum values of the following function on the given curves. use the parametric equations x=2cos t, y 2 sin t functions: curves: i) the semicircle x4,y20 i) the quarter circle x2+y-4, x20, y20 b, g(x,y)=xy