Pie Graph.
a "circle graph" is also a polar graph, it's used to graph polar coordinates.
the firt and second graph should be circled 2. the bar graph 3. the line graph
The mathematical technique used to calculate the area under a graph is integral calculus. This is a complex subject which I am not going to attempt to explain in detail- it normally takes years of study.
Line Graph, and I know that these are Study Island questions.
One graph used to relate stars' absolute magnitudes and their spectral types is the Hertzsprung-Russell diagram, better (and more simply) known as the H-R diagram.
Pie Graph.
telescopes
Telescopes
The study of the stars is astronomy.
Spectroscope
Why did Asians study stars
Arecibo
People in the past usually studied the stars because they used it to make Calenders and days
The proper name for the study of stars is astronomy. A person who studies stars is an astronomer.
Hertzsprung-Russell diagram. This diagram plots a star's luminosity against its temperature (or color), allowing scientists to classify stars by size, brightness, and lifecycle stage.
An observatory is a location used for observing terrestrial and/or celestial events