PLEASE HELP! 100 POINTS FOR 3 MATH QUESTIONS.
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Describe all the numbers that when rounded to the nearest thousand are 645,000

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angles. measure need asap

The equation of a circle is (x + 4)2 + (y + 6)2 = 16. determine the length of the radius. 10 4 16 8 my flower basket delivers flowers within a 20 mile radius of their store. if this area is represented graphically, with my flower basket located at (5, 2), what is the equation that represents the delivery area? (x - 2)2 + (y - 5)2 = 20 (x - 5)2 + (y - 2)2 = 20 (x + 5)2 + (y + 2)2 = 400 (x - 5)2 + (y - 2)2 = 400