Answer:
Arc length ![=\int_0^{\pi} \sqrt{1+[(4.5sin(4.5x))]^2}\ dx](https://tex.z-dn.net/?f=%3D%5Cint_0%5E%7B%5Cpi%7D%20%5Csqrt%7B1%2B%5B%284.5sin%284.5x%29%29%5D%5E2%7D%5C%20dx)
Arc length 
Step-by-step explanation:
The arc length of the curve is given by ![\int_a^b \sqrt{1+[f'(x)]^2}\ dx](https://tex.z-dn.net/?f=%5Cint_a%5Eb%20%5Csqrt%7B1%2B%5Bf%27%28x%29%5D%5E2%7D%5C%20dx)
Here,
interval ![[0, \pi]](https://tex.z-dn.net/?f=%5B0%2C%20%5Cpi%5D)
Now, 
![f'(x)=\frac{\mathrm{d} }{\mathrm{d} x}\left ( [-cos(t)]_0^{4.5x} \right )](https://tex.z-dn.net/?f=f%27%28x%29%3D%5Cfrac%7B%5Cmathrm%7Bd%7D%20%7D%7B%5Cmathrm%7Bd%7D%20x%7D%5Cleft%20%28%20%5B-cos%28t%29%5D_0%5E%7B4.5x%7D%20%5Cright%20%29)


Now, the arc length is ![\int_0^{\pi} \sqrt{1+[f'(x)]^2}\ dx](https://tex.z-dn.net/?f=%5Cint_0%5E%7B%5Cpi%7D%20%5Csqrt%7B1%2B%5Bf%27%28x%29%5D%5E2%7D%5C%20dx)
![\int_0^{\pi} \sqrt{1+[(4.5sin(4.5x))]^2}\ dx](https://tex.z-dn.net/?f=%5Cint_0%5E%7B%5Cpi%7D%20%5Csqrt%7B1%2B%5B%284.5sin%284.5x%29%29%5D%5E2%7D%5C%20dx)
After solving, Arc length 
Answer:
x = (√21)/2
Step-by-step explanation:
The sides of a 30°-60°-90° triangle have the ratios 1 : √3 : 2. That means the middle-length side is (√3)/2 times the length of the longest side.
x = (√3)/2·√7

Break down the figure into 2 separate rectangular solid and find each volume and sum it.
<u>Volume of smaller step:</u> The volume of any rectangular solid is given by,

So we have 
<u>Volume of larger step:</u> The only dimension that is different than the smaller step is of the height, which is 6. So we have,

Hence, the volume of the whole figure, in cubic inches, is
. Answer choice B.
ANSWER: B
Answer:
good
those desert people ought to use less water