All straight lines measure 180 degrees. In the diagram below, the straight line EF contains three angles, < 3, <4, and <5. If <3 is 90 degrees. What is the measurement of <4 + <5 = _________?

A. 180 degrees

B. 90 degrees

C. 45 degrees

This requires a diagram.

Assuming that < 3, <4, and <5 are adjacent and together form a straight angle along EF,

<3 + <4 + <5 = 180
But, <3 = 90
=> 90 + <4 + <5 = 180
=> <4 + <5 = 180 - 90 = 90

To find the measurement of <4 + <5, we need to first understand some geometry concepts.

In this case, we are dealing with straight lines and angles formed by intersecting lines. When a straight line intersects with another line, it creates pairs of opposite angles that are equal. These angles are called vertical angles.

Looking at the diagram, we can see that <3 and <4 are vertical angles. Since <3 measures 90 degrees, we know that <4 also measures 90 degrees.

Now, to find the measurement of <4 + <5, we simply need to add the measures of <4 and <5. Since <4 is 90 degrees and <5 is not given any measurement, we cannot determine the exact value of <4 + <5.

Therefore, the answer to the question is:

D. We cannot determine the measurement of <4 + <5 based on the given information.