If we set the mass of the Earth as 1.0 we can then list the masses of all of the traditional planets in our solar system in terms of number of Earth masses (rather than a bazillion kg or whatever). The following table lists the masses of the 9 planets in our system in Earth masses.

Planet Mass (in 'earths)

Mercury .055

Venus .815

Earth 1.0

Mars .107

Jupiter 318

Saturn 95.2

Uranus 14.6

Neptune 17.2

Pluto .002

a) What is the average mass of the planets of our solar system?

b) Are there any outliers? Back up your assertion with evidence

c) What is the variance of the masses of the planets?

d) The inner planets (Mercury, Venus, Earth and Mars) seem to be quite a bit smaller than the four gas giants (Jupiter, Saturn, Neptune and Uranus). Are they significantly different?