The Earth orbits around the sun. Which scenario would cause the greatest increase in gravitational forces between the 2 masses?
A- Double the distance between the Earth and sun
B- Reduce the distance between the Earth and the sun in half.
C- Double the Earth's size.
D- Reduce the sun's size by half.

The flame produced by the burner of a gas (propane) grill is a pale blue color when enough air mixes with the propane (c3h8) to burn it completely. for every gram of propane that flows through the burner, what volume of air is needed to burn it completely? assume that the temperature of the burner is 195.0°c, the pressure is 1.05 atm, and the mole fraction of o2 in air is 0.210.