Someone
in the figure, m and n are midpoints of rt and st. what is the length of mn?

a + b
b - a
2

So the correct answer is option B- ( b - a )

Step-by-step explanation:

Given that M and N are the mid-points of RT and ST.

We are to find the length of MN.

As shown in the figure,

the co-ordinates of the point T are (2c, 2d),

the co-ordinates of the point S are (2b, 0),

and

the co-ordinates of the point R are (2c, 2d).

Since M is the mid-point of TR, so the co-ordinates of M are

=(c+a,d).

Also, N is the mid-point of TS, the co-ordinates of N are

=c+b,d)(.

Therefore, the length of the line segment MN calculated using distance formula will be

MN==b-a.

Thus, the required length of MN is (b - a) units.

Option (B) is correct.

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step-by-step explanation:

the answer is; biodiversity resulting from few ancestors

adaptive radiation occurs when a population is subjected to a large natural environment with spatial ecological variations. the parts of the population in the different ecologies begin to adapt to their local environments. due to non-random mating across the large populations, this causes the different populations from the large population to speciate within their local environments. they, therefore, diverge to different species sharing a common ancestor.