A rain drop hitting a lake makes a circular ripple. If the radius, in inches, grows as a function of time in minutes according to r(t) = 25/t + 2, find the area of the ripple as a function of time. Find the area
of the ripple at t = 2.
Enter the exact answer. For the number 7, you can either type pi or you can click the button with it on
it.

Add, subtract, multiply, or divide as indicated. list any restrictions for the variable(s) and simplify the answers when possible. 1) x-2 / x+5 + 3x / 2x-1 2) x+6 / x-6 - x^2 / x+6 3) x+9 / x-4 + x+2 / x^2-11x+28 4) x / x^2-64 + 11 / 2x^2+11x-40 5) 5 / x + 11 / x-3 - x-4 / x^2+2x-15

Arandom sample of n = 25 observations is taken from a n(µ, σ ) population. a 95% confidence interval for µ was calculated to be (42.16, 57.84). the researcher feels that this interval is too wide. you want to reduce the interval to a width at most 12 units. a) for a confidence level of 95%, calculate the smallest sample size needed. b) for a sample size fixed at n = 25, calculate the largest confidence level 100(1 − α)% needed.

What does the quadrilaterals on a kid with her art class it is possible to draw a parallelogram that is not a rectangle explain