Atwo-story building measures 21 feet from the ground. ascale model shows the building to be 3 inches tall. how many inches would an 84 foot building be in the model?

Step-by-step explanation:

Let be "x" the height inches (in the model) of a 84 foot building.

According to the information provided in the exercise, we know that the height of a two-story building is 21 feet and in the scale model its height is 3 inches.

Knowing this, we can set up the following proportion:

The final step is to solve for "x" in order to calculate its value. We get that this is:

Therefore,  an 84 foot building will be 12 inches tall in the model.

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.  

b. would be the answer : )

step-by-step explanation:

step 1: add -16x to both sides.

16x−4y+−16x=64+−16x  

−4y=−16x+64

step 2: divide both sides by -4.

−4y /-4 = -16x + 64/-4

answer:   y=4x−16

hope i'm right