Answer:
The correction is D
Step-by-step explanation:
From the question we are told that
The maximum height is [tex]h_m = 18 ft[/tex]
The minimum height is [tex]h_i = 4 ft[/tex]
The function that models the height of the blade is [tex]h(x) =- 14 sin(x) + 18[/tex] here x is time in seconds
Now at maximum height
[tex]18 = - 14 sin(x) + 18[/tex]
=> [tex]-14 sin(x) =0[/tex]
=> [tex]sin(x) =0[/tex]
=> [tex]x =sin^{-1}[0][/tex]
=> [tex]x =0 \ s[/tex]
Now at minimum height
[tex]4 = -14 sin(x) + 18[/tex]
=> [tex]-14 = -14 sin(x)[/tex]
=> [tex]sin (x) = 1[/tex]
=> [tex](x) = sin^{-1}[1][/tex]
=> [tex]x = 1.6 \ s[/tex]
Now this values is the time taken to move from the higher position of the blade to the lower position of the blade
Now it will take this same amount of time to complete the circle
So the total time take is
[tex]x_t = 2 * |x|[/tex]
=> [tex]x_t = 2 * 1.6[/tex]
=> [tex]x_t = 3.2 \ s[/tex]
