Answer:
In the episode pertaining to the discovery of radium, it is false that all of the hypotheses turned out to be true.
There are some hypotheses in the episode thay turned out to be false.
I think it’s the last one I am not sure tho
We know the perimeter is the total sum of all sides of the shape, we can use this to form an equation: the perimeter=1st side + 2nd side + 3rd side + 4th side 39a-7=9a+(5a+1)+(17a-6)+4th side.
Collect like terms to get 39a-7=31a-5+4th side
If we move everything but the 4th side over to the left we can solve
C. 8a-2=4th side is the correct answer