Answer:
64.3 lumens
Step-by-step explanation:
Data provided in the question:
Length of the testing chamber = 35 cm
Light at one end = 10 lumens
Light at other end = 200 lumens
now,
since the variation is linear,
therefore, the gradient of the variation
= 
= 5.43
also,
the darkest end is the end with 10 lumens
therefore,
The lumens at 10 cm from the darkest end
= 10 + 5.43(10)
= 10 + 54.3
= 64.3 lumens
The answer is 1.2 b/c you have to solve x by simplifying both sides of the equation and isolating the variable.
6x2 + x - 7
= (6x + 7)(x - 1)
So, the answer is (6x + 7), or C.