The number of permutations of the 26 letters of the English alphabet that do not contain any of the strings fish, rat, or bird is 402619359782336797900800000
Let

Then

Note that since 
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, 
But since
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, 
and
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Since

where 
and

What we are looking for is the number of permutations of the 26 letters of the alphabet that do  not contain the strings fish, rat or bird, or

This link contains another solved problem on permutations:
brainly.com/question/7951365
 
        
             
        
        
        
First: Slope of -x+2y=42y=x+4y=x/2+2So, m=1/2.
Second: Slope  of the perpendicular line: mp=-2.
Third: Find the line with slope -2 and passes through the point (−2, 1)y-y1=m(x-x1)y-1=-2(x+2)y=-2x-4+1y=-2x-3 
Read more on Brainly.com - 
brainly.com/question/7942650#readmore
 
        
        
        
Ans: (c)
y = k/x^2
when y = 100, x = 1
100 = k/1^2
k = 100
when x = 2,
y = 100/2
= 50 
(u/rachelmarrons already gave you the answer but here’s a step-by-step explanation in case you needed it haha)
        
             
        
        
        
Answer:
option a)
y = m(0.5) + 1.8
Step-by-step explanation:
Equation 
<h3>
y = mx + c</h3>
represent the equation of straight line 
here m = gradient of straight line
          c = y-intercept 
First find the gradient of the graph
<h3>
m = y2 - y1 / x2 - x1</h3>
     = 4 - 3 / 4 - 2 
     = 1 / 2
Put the values in the equation of straight line
y =mx + c
4 = 1/2(4) + c
c = 2
y = 1/2x + 2
which is approximately equal to y = 0.5x + 1.8
 
        
             
        
        
        
I'm not sure I understand your question, but I believe the answer you're looking for is 57632.