Answer:
D) sudden and irresistible on sets of sleep during normal waking periods
Explanation:
D because Narcolepsy (sudden and irresistible on sets of sleep during normal waking periods) is a part of insomnia
Observe that the given vector field is a gradient field:
Let 
, so that
Integrating the first equation with respect to 
, we get
Differentiating this with respect to 
gives
Now differentiating 
with respect to 
gives
Putting everything together, we find a scalar potential function whose gradient is 
,
It follows that the curl of is 0 (i.e. the zero vector).
Double Displacement Reaction
An element from each of two compounds switch places.
Example: compound + compound ⇒ compound + compound
Chemical reactions are processes in which substances change into other substances. A chemical reaction takes place if one or more of these occur:
Color changes - Different combinations of molecules reflect light differently. A color change indicates a change in molecules.
Heat content changes- In all chemical reactions, the heat content of the reactants and the heat content of the products is never the same. Sometimes the difference is great and can be easily detected. At other times, the difference is slight and more difficult to detect.
Gas produced - Whenever a gaseous product forms in a liquid solution, bubbles can be seen. A colorless gas produced in a reaction of solids is much harder to detect.
Precipitate forms- Precipitates are insoluble products formed by a reaction taking place in a liquid solution. This insoluble product will eventually settle to the bottom, but might immediately appear by turning the clear solution cloudy.
I think this is the answer:
<span>Matter can change its state because of the pressure and/or the temperature.</span>
Explanation:
Power output of the bulb:
0.021 × 60 W = 1.26 W
Energy produced by the bulb in 1 second:
E = Pt
E = (1.26 W) (1 s)
E = 1.26 J
Round as needed.
