The constant is "4.5 miles per hour", or whatever the actual units are.
The answer for this question is choice c. Memorization is not a good way to truly understand math. You want to understand the reasoning behind your answers always.
A math expert is what you should strive to be! The first two choices are great ways to become this.
Answer:
√5
Step-by-step explanation:
We suppose the vertices are named clockwise around the top of the cube, then clockwise around the bottom (looking down from above the cube), with vertex E below vertex D. Then line AD is in plane ADEF, and line BM is in plane BCHG.
The distance between the named parallel planes is the distance between the lines. That distance is AB, which is given as √5.
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A diagram helps.
