This isn't a math question and should be in the science section. However, I will still answer the question. The answer is choice B.
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Here's a further breakdown
A. False. The radiation or energy from the sun can travel through air or else you wouldn't feel the sun's rays. Also, plant life wouldn't be alive without that energy going through the air.
B. True. The rays travel through a vacuum of space. If they couldn't travel through space, then the same problem comes up as in choice A: the issue of not feeling the sun's rays.
C. False. They rays have different frequencies. Because there are many wavelengths (see choice D below), this means there are different frequencies. Recall that f = 1/w where f is the frequency and w is the wavelength.
D. False. The rays are made of different wavelengths. The visible light portion is what we can see, though there is a lot more to the electromagnetic spectrum (eg: ultraviolet light).
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So once again, the answer is choice B
Answer: The slope of the line that passes through (2, 12) and (4, 20) is 4.
The value of the y-intercept is 9.
Step-by-step explanation:
Slope of line passing through (a,b) and (c,d) = 
Then, the slope of the line that passes through (2, 12) and (4, 20) = 
So, the slope of the line that passes through (2, 12) and (4, 20) is 4.
To find the y-intercept of 3x + 2y = 18, first write in slope intercept form y=mx+c ( where c= y-intercept ).
By comparison, c= 9
Hence, the value of the y-intercept is 9.
Solution:
Given,
Volume of the-
First cube box=1728 in³
Second cube box=13824in³
We know that volume of cube =a³
So for the first box
a³= 1728 in³
a= 12 in
Now, surface area of the first box
6a²= 6×(12)²
= 864 in²
and for the second box
b³= 13824 in³
b= 24 in
Now, the surface area of the second box
6b²= 6×(24)²
= 3456 in²
Now, the ratio of the surface area of first box to the second box will be
864:3456
=1:4
The surface area of the larger of two boxes is
3456 in²
Answer:
10 milligrams of Medication A
Step-by-step explanation:
We'll write proportions/ratios for this:
20:16 is the usual proportion, and x:8 is this week's dose. The ratio from A to B has to be equal, so
20/16 = x/8
Cross-multiply:
(20)(8) = (16)(x)
160 = 16x
divide both sides by 16
x = 10
Please let me know if you have questions about this answer.
Let the youngest sister be n years
Lana will be 2n years, as her youngest sister is half her age
The age of the twins separately will be 2n-2 as they are 2 years younger than Lana
So, the equation looks like this:
n + 2n + 2(2n-2) = 45
Now solve for n:
3n + 4n - 4 = 45
7n - 4 = 45
7n = 49
n = 7
So the youngest sister is 7, Lana is 14 and the twins are 12. 14 + 12 + 12 + 7 =45
