The red star in the right top portion of this picture is Betelgeuse, one of the most prominent stars in the constellation Orion. You can easily see this constellation during winter in the northern hemisphere. Betelgeuse is a red supergiant star which is ~ 634 light years from Earth. To measure the surface temperature of stars astronomers use Wien's law which relates the maximum wavelength of light emitted to the temperature. Mathematically Wien's law is written {\lambda}_{max}T = 0.2898 cm K. Betelgeuse has a {\lambda}_{max} of 8072 Å where 1 Å = 1 x 10^{−8} cm. What is Betelgeuse's surface temperature, in K? [Image description: The picture is of the night sky. Thousands of stars are shining. Some are red, some white and some blue.]

Electromagnets coils of wire paper clips picked up 10 3 15 6 20 9 25 12 ms. owens' class was studying magnets. ms. owens showed her students how to make an electromagnet using a nail, a d-cell battery, and plastic coated wire. the students wrapped the wire around the nail and then attached the ends to the battery. when they were finished, they tested their magnets by investigating how many paperclips their magnets could pick up. they also tested whether they could increase the strength of their electromagnets by using more coils of wire. they recorded the class average of their results in the data table seen here. ms. owens asked her students to graph their data in a line graph. how should the students label the x-axis on their line graph? a) size of battery b) number of paper clips c) number of coils of wire d) strength of electromagnet