Let the charge density in a certain region of space be ?. The electric field 
in that region points in the +x direction with 
increasing as x increases. This implies
A. that ? is positive in that region.
B. that ? is negative in that region.
C. that ? is zero in that region.
D. that the field is physically impossible.
E. nothing useful about the charge density.
A. that ? is positive in that region.
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A. concave mirror farther than one focal length from the burning candle. B. a convex mirror farther than one focal length from the burning candle. C. a biconcave lens farther than one focal length from the burning candle. D. a concave mirror closer than one focal length to the burning candle. E. a convex lens closer than one focal length to the burning candle.
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