∠ach = 115° ∠gbf = 35° what is the degree measure of ∠a?

∠ACB is a Supplementary angle to ∠ACH. Supplementary angles must equal 180 degrees.

∠ACB = 180 - 115 = 65 degrees.

∠ABC is a vertical angle of ∠GBF, which means they are identical, so ∠ABC is 35 degrees.

The three inside angles of a triangle must equal 180 degrees.

∠A = 180 - 65 - 35 = 80 degrees

A straight line is 180°. So you can do:

∠ACH + ∠ACB = 180°  (you can do∠ACG or ∠ACB, doesn't matter)

This is because ∠ACH and ∠ACB make up a 180° angle(straight line)

∠ACH + ∠ACB = 180°  Since you know ∠ACH, you can plug it in

115° + ∠ACB = 180° Subtract 115 on both sides to find ∠ACB

∠ACB = 65°

The ∠GBF should be equal to ∠ABC, so ∠ABC = 35°

This is because opposite angles are congruent/identical (equal)

A triangle is also 180°.

Now that you know the angle of C and B, you can do this:

65° + 35° + ∠A = 180°

100° + ∠A = 180° Subtract 100 on both sides

∠A = 80°

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.