Only answer if you're very good at math. No guessing please. A ferris wheel rotates around in 30 seconds. The maximum height above the ground is 55 feet, and the minimum height above the ground is 5 feet. Which function models the height as a function of t in seconds?

A: f(t) = 25sin π/15t + 30

B: f(t)= 30sin π/15t+25

C: f(t) = 25sin 2πt + 30

D: f(t)= 25 sin 60πt + 30​

it costs $20 to interview each person for a survey. find the cost to obtain a +- 3% margin of error.

step-by-step explanation:

copy and paste, put it in google

step-by-step explanation:

b and c

answer: 204

step-by-step explanation:

we are told that the revenue is

x⋅(4080−10x)=−10x^2+4080x

this is a quadratic function, so to maximize it we should find the x-value of its vertex. recall that the x-value of the vertex of the parabola ax^2+bx+c is given by the formula −b/2a.

so in this case, we have a=−10 and b=4080, so the x-value of the vertex is

−b/2a= −(4080)/2(−10)=204