Lim ln(tan x) as tends to pi/2 from the left

Given that de, df, and ef are midsegments of △abc, and de=3.2 feet, ef=4 feet, and df=2.4 feet, the perimeter of △abc is .

Which of the following is most likely the next step in the series? a3z, b6y, c9x, d12w, е15v, f18u

Choose the number sentence that shows the identity property of addition. a. 122 = 61 + 61 b. 62 = 1 + 61 c. 61 = 0 + 61