Answer:
Option B. AA
Step-by-step explanation:
we know that
Angle-Angle (AA) Similarity Postulate, states that If two angles of one triangle are congruent to two angles of another, then the triangles must be similar
In this problem
<em>In the triangle XYZ</em>
∠X=70°
∠Y=90°
∠Z=90°-70°=20° (remember that angle X and angle Z are complementary)
<em>In the triangle UWV</em>
∠V=20°
∠W=90°
∠U=90°-20°=70° (remember that angle V and angle U are complementary)
therefore
Traingles XYZ and UWV are similar by AA Similarity Postulate
Answer:
81.85% of the workers spend between 50 and 110 commuting to work
Step-by-step explanation:
We can assume that the distribution is Normal (or approximately Normal) because we know that it is symmetric and mound-shaped.
We call X the time spend from one worker; X has distribution N(μ = 70, σ = 20). In order to make computations, we take W, the standarization of X, whose distribution is N(0,1)

The values of the cummulative distribution function of the standard normal, which we denote
, are tabulated. You can find those values in the attached file.

Using the symmetry of the Normal density function, we have that
. Hece,

The probability for a worker to spend that time commuting is 0.8185. We conclude that 81.85% of the workers spend between 50 and 110 commuting to work.