if a weather map has a symbol that shows a circle with an h in the middle, what is it
referring to?

a.) high pressure
b.) high weather
c.) high temperature
d.) humid weather

Can someone me with questions 15 to 17 plz.

Look at the spectrums of a star moving towards earth and a motionless star. which of these is a correct inference that can be draw from the observation of the two spectrums? (2 points) the spectrum of a motionless star is difficult to be viewed separately using oridinary telescopes. the spectrum of a motionless star is identical to the spectrum of a star which moves towards earth. the spectrum of a star shifts towards the red region when the star moves towards earth. the spectrum of a star shifts towards the blue region when the star moves towards earth.

Which is an example of a highly unstable isotope that is often used in fission reactions?