10 less than the product of 8 and 5

Which of the following equations is of the parabola whose vertex is at (2, 3), axis of symmetry parallel to the y-axis and p = 4? a.)y-3 = 1/16 (x-2)^2 b.)y+3 = -1/16 (x+2)^2 c.)x-2 = 1/16 (y-3)^2

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The circumference of a redwood tree trunk is 20π ft, and it is 100 ft tall. what is the approximate volume of the redwood tree trunk? 1,000π ft3 10,000π ft3 4,000π ft3 40,000π ft3