Astudent says that since the atomic theory is just a theory, it should not be considered useful. which statement best argues against the student’s opinion?

Which sentences describe disadvantages of burning fossil fuels instead of using hydrogen fuel cells? burning fossil fuels contributes to climate change. burning fossil fuels takes place inside expensive fuel cells. fossil fuels aren't widely available, but pure hydrogen is. fossil fuels are nonrenewable.

Select the word from the list that best fits the definition classification of most stars on the h-r diagram

Awave is produced in a rope. the wave has a speed of 33 m/s and a frequency of 22 hz. what wavelength is produced?