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Let f(x) = x4- 8x2 . find the relativeextrema of this function using the second derivative test.

Awater slide of length l has a vertical drop of h. abby's mass is m. an average friction force of magnitude f opposes her motion. she starts down the slide at initial speed vi. use work-energy ideas to develop an expression for her speed at the bottom of the slide. then evaluate your result using unit analysis and limiting case analysis. express your answer in terms of the variables h, m, l, vi, f and appropriate constants. vf v f

The voltmeter reads 117 v and ammeter reads 0.13 a .if the resistance of ammeter and voltmeter are 9 kilo ohm and 0.015 ohm respectively ,find the value of r. 3marks