Answer:
The answer is the mutations within the genetic code.
Step-by-step explanation:
Natural selection is one of the basic mechanisms of evolution by which species adapt to their environment in order to increase their chance of survival and reproduction. In natural selection, genotype variations that will increase the chance of survival and reproduction of some organism are preserved and will be inherited. But, the sources of this genotype variations are not changes in the environment, nor response to the stress, but the mutations in the genome of the organism. If a mutation is not lethal, it could remain in the population, increasing the variation is some traits.
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Two numbers that gives twice the sum of a number and 3 times a second number is 4. The difference of ten times the second number and five times the first is 90 are -10 and 4
Given :
Twice the sum of a number and 3 times a second number is 4. The difference of ten times the second number and five times the first is 90.
Let a and b be the two unknown numbers
Lets frame equation using the given statements
Twice the sum of a number and 3 times a second number is 4.

the difference of ten times the second number and five times the first is 90

Now use these two equations to solve a and b

Add both the equations

Now find out 'a'

The two numbers are -10 and 4
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Answer:
The probability that a call last between 4.2 and 4.9 minutes is 0.4599
Step-by-step explanation:
Let X be the length in minutes of a random phone call. X is a normal distribution with mean λ=4.2 and standard deviation σ=0.4. We want to know P(4.2 < X < 4.9). In order to make computations, we will use W, the standarization of X, given by the following formula

We will use
, the cummulative distribution function of W. The values of
are well known and the can be found in the attached file

We conclude that the probability that a call last between 4.2 and 4.9 minutes is 0.4599
Answer:
Step-by-step explanation:
65.00 - 31.25 - 16.50 = $17.25