I believe there are three carbon atoms in propane
The Sun, like most other astronomical objects (planets, asteroids, galaxies, etc.), rotates on its axis. Unlike Earth and other solid objects, the entire Sun doesn't rotate at the same rate. ... The Sun's rotation rate decreases with increasing latitude, so that its rotation rate is slowest near its poles.
I believe it is B writing chemical formulas
For the first question the answer is
The "s" orbital can only hold a maximum of two electrons. ... Elements in the each group have the same number of valence electrons. Why is hydrogen set apart by itself? Hydrogen does not belong to a single group b/c it can be considered an alkali metal, but it is also a gas.