<span>Frederick Griffith
built up that there was a </span>transforming principle<span> in bacterial hereditary qualities in a pivotal
investigation in 1928 and was the main trial recommending that microorganisms
are fit for exchanging hereditary data through a procedure known as transformation.
The exact idea of the transformation principle (DNA) was confirmed in the
investigations done by Avery, McLeod, and McCarty and by Hershey and Pursue.</span>
If you have samples of n 1 equals 22 and n 2 equals 20, in performing the pooled-variance t test, you have 40 degrees of freedom.
The t-test method is a method where we analyze two sets of data which both these data are independent of each other. This pooled variance test helps us in getting the overall variance in both these different sample sets when we know that both the sample sets are almost equal.
To calculate degrees of freedom, we have the formula
df = n1 +n2 -2
According to the question, n1= 22 and n2= 20
Therefore, degree of freedom= 22 +20 -2 = 40
Hence, degree of freedom is 40.
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A. voting rights could not be denied based on race.
B. voting rights could not be denied based on gender.
C. poll taxes became illegal and unconstitutional.
D. literacy tests became illegal and unconstitutional.
The fifteenth amendment states that "The right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of <em>race</em>, <em>color</em>, or <em>previous condition of servitude</em>."
There was no mention of gender, so voting for women hadn't been legalized until 1919, making B wrong.
ANSWER: (D) or aka the 4th option
EXPLANATION:
On September 11, 2001, 19 militants associated with the Islamic extremist group al Qaeda hijacked four airplanes and carried out su**ide attacks against targets in the United States.
You can also look it up online for more details.
