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

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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
Answer: 90°
Step-by-step explanation:
Angle b is vertical to the angle that has a measure of 90°
Answer:
1+1=2
2+2=4
4+3=7
7+4=11
so the patter is number + natural numbers (serially)
Step-by-step explanation:
Answer:
The SI unit for length is the meter (abbreviated m); its definition has also changed over time to become more accurate and precise. The meter was first defined in 1791 as 1/10,000,000 of the distance from the equator to the North Pole.