What are the names of all of the valves in the heart? Check all that apply
ventricular valve
aortic valve
atrium valve
carotid valve
mitral valve
pulmonary valve
tricuspid valve

Nuclear fusion is the source of energy for stars. besides hydrogen, which other element is most likely also common in stars?

The yearly amounts of carbon emissions from cars in belgium are normally distributed with a mean of 13.9 gigagrams per year and a standard deviation of 5.8 gigagrams per year. find the probability that the amount of carbon emissions from cars in belgium for a randomly selected year are between 11.5 gigagrams and 14.0 gigagrams per year. a. 0.340 b. 0.660 c. 0.167 d. 0.397

What produces wave a)sound b) heats c)transfer of energy d)vibrations