Answer:
c)is unique to that element
Explanation:
The spectrum emitted by a element shows the internal electronic structure of that element.We know that all element is having different internal electronic structure that is why all element emits different spectrum.And the spacing between the spectrum is uneven .
Therefore the answer will be option C.
c)is unique to that element
Answer:
Removing some of the books reduced the mass of the box, and less force was needed to push it across the floor.
Answer:
T=575.16K
Explanation:
To solve the problem we proceed to use the 1 law of diffusion of flow,
Here,

is the rate in concentration
is the rate in thickness
D is the diffusion coefficient, where,

Replacing D in the first law,

clearing T,

Replacing our values



You should select Choice-4 .