The second most abundant element in the solar system is
A) silicon. B) helium. C) oxygen. D) hydrogen. E) carbon.
Question 2
How do we know the expansion of the universe is accelerating?
A) We're really not that sure the expansion is accelerating; it's all just a theory.
B) The rotation curves of galaxies indicate the universe is speeding up.
C) White dwarf supernova in distant galaxies are fainter than they would be if the expansion were not accelerating.
D) Redshifts of distant galaxies are increasing with time, so when we repeat the measurements, the redshifts are larger.
E) We see more of the universe every night, as the observable universe grows in size.
Motion of the barycenter of the Solar System relative to the Sun
Female genital and reproductive system.
Female Reproductive system
What Happens to Incoming Solar Radiation?
Landsteiner's experiment demonstrating the exquisite specificity of the immune system.
Relationship of Sun Angle and Solar Radiation