Answer:
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Step-by-step explanation:
and @wtfpeachess
It is approximately 1.000
we can use formula

where
fL is listener frequency
fs is siren frequency
va is the speed of sound in air
vs is police car speed
so, we have



now, we can change it into m/s


now, we can plug it

..............Answer
Answer:
400%
Step-by-step explanation:
Let the sales be "100" in 1994
Since, it decreased 80%, the sales was:
80% = 80/100 = 0.8
0.8 * 100 = 80 (decreased by 80)
So, it was
Sales in 1995: 100 - 80 = 20
Sales in 1996 was same as in 1994, so that's 100
Thus,
Sales in 1994: 100
Sales in 1995: 20
Sales in 1996: 100
We need to find percentage increase form 1995 to 1996, that is what percentage increase is from 20 to 100?
We will use the formula:

Where
New is 100
Old is 20
SO, we have:

So, it increased by 400%
Answer:
The Laplace transform of f(t) = 1 is given by
F(s) = (1/s) for all s>0
Step-by-step explanation:
Laplace transform of a function f(t) is given as
F(s) = ∫∞₀ f(t) e⁻ˢᵗ dt
Find the Laplace transform for when f(t) = 1
F(s) = ∫∞₀ 1.e⁻ˢᵗ dt
F(s) = ∫∞₀ e⁻ˢᵗ dt = (1/s) [-e⁻ˢᵗ]∞₀
= -(1/s) [1/eˢᵗ]∞₀
Note that e^(∞) = ∞
F(s) = -(1/s) [(1/∞) - (1/e⁰)]
Note that (1/∞) = 0
F(s) = -(1/s) [0 - 1] = -(1/s) (-1) = (1/s)
Hope this Helps!!!