Can you guys help me on this please

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Find the condition that the zeros of the polynomial f(x) = x^3+3px^2+3px+r may be in a.p.

Which of the following represents the length of a diagonal of this trapezoid?

The angle of depression from the top of the tree to the tip of the shadow is 25°. find the height of the tree to the nearest tenth. a. 16.8 feet b. 18.2 feet c. 23.4 feet d. 39.7 feet