Answer:
<em>120 degrees</em>
Step-by-step explanation:
Find the diagram attached.
From the diagram;
Interior angles are m∠BCA and m∠ABC
Exterior angle is m∠DAB
The sum of interior angle of the triangle is equal to exterior
m∠BCA +m∠ABC =m∠DAB
Given
m∠ABC = 70
m∠BCA =50
m∠DAB = 70 + 50
m∠DAB = 120 degrees
<em>Hence the measure of m∠DAB is 120 degrees</em>

The degree of f(x) is 4. Also the leading coefficient is 1 and it is positive
So as x approaches infinity then y approaches infinity
as x approaches -infinity then y approaches infinity
The first and fourth graph goes up and it satisfies the above . so we ignore the second and third graph.
Now we check the x intercepts of the first graph
x intercepts of first graph is -4 and 2
Plug in -4 for x in f(x) and check whether we get 0


Now plug in 2 for x and check

So -4 and 2 are the x intercepts that satisfies f(x)
Hence first option is the graph of 
Electricity travels at 186,000 MPS
Okay, do you have an equation for me to solve
I'm assuming its asking what time he finished? I added it up and it seems to be 7:42 pm.