<span>B. shining a bright light on the objects
and testing for decomposition </span>
<span>
In explanation, chemical property is a
characteristic of a certain substance came from an outcome due to chemical change
or reaction. In the situation above, more specifically toxicity is involved in
the chemical property/change. Hence, when the object is tested for
decomposition. Like for an example of decomposition simply in metals, rusting. Rusting
a process of degeneration of metals. Here it works the same. Toxicity is how
much damage did a certain entity do to the object. </span>
Explanation:
It is given that,
Frequency of monochromatic light, 
Separation between slits, 
(a) The condition for maxima is given by :

For third maxima,



(b) For second dark fringe, n = 2





Hence, this is the required solution.
Answer:
The VSEPR theory and how it predicts the shapes of molecules:
Explanation:
The Valence Shell Electron Pair Repulsion (VSEPR) theory is a model used in chemistry to predict the shapes of individual molecules by the number of electron pairs that they have in the center of the atom. This theory is also based on the notion that the electrons around the atom repel one another. The Valence electrons on the outermost layer of the molecule are the most important in defining the geometry as they are the first to interact with other atoms and will be involved in bonding.
Answer:
A.The spring constant for B is one quarter of the spring constant for A.
Explanation:
If spring A oscillates at twice the frequency of spring B, and period is frequency inverted. It means spring B has a period twice of spring A's.

As
, and the 2 springs have the same mass




So A.The spring constant for B is one quarter of the spring constant for A. is the correct answer.