Final answer:
To find the measure of ∠BDC, we need to use the concept of similar triangles.
Step-by-step explanation:
To find the measure of ∠BDC, we need to use the concept of similar triangles. From the given information, we know that the flash occurs 100 miles above Earth at point C. Let's assume that the distance from point C to the Earth's surface at point B is x miles.
Since we have a right triangle, we can use the tangent function to calculate the angle ∠BDC. Tan(∠BDC) = Opposite/Adjacent = (100/x). Rearranging the equation, we have x = 100/tan(∠BDC).
Now, we can use the given range of 50 to 200 miles to find the possible values of ∠BDC. By substituting different values of x in the equation, we can calculate the corresponding values of ∠BDC.