This is only the first part, where's the rest?
The answer is {4, 6, 8, 10, 12} - or B
Wave Speed = Wave Frequency x Wavelength
You know that the speed of radio waves in a vacuum is 3x10^8 m/s
so you just substitute the values into the equation below.
Wavelength = Wave Speed / Wave Frequency
Wavelength = 3x10^8 / 5x10^9
Wavelength = 0.06 m
The equation is in the format
where a is the initial value (when t=0), b is the rate of change between terms, and t is the amount of time.
Our initial value is 100. We find the rate of change by first finding the percent of change:
amount of change/original amount
= 20/100 = 0.2
This is a percent decrease, so we will subtract it from 1:
1-0.2 = 0.8
This goes in for b.
Answer:
D. 25pi
Step-by-step explanation:
"circumscribed" means the rectangle is inside the circle and just the corners (vertices) of the rectangle are touching the circle. This means the diagonal of the rectangle is the diameter of the circle. See image. If the sides of the rectangle are 6 and 8 then the third side that makes the triangle(half the rectangle) is 10. You can find this using Pythagorean Theorem or Pythagorean triples (shortcut)
6^2 + 8^2 = d^2
36 + 64 = d^2
100 = d^2
d = 10
This is the diameter of the circle. The radius would then be 5.
Area of a circle is:
A = pi•r^2
= pi•5^2
= 25pi