Just how massive are nebulae? Nebulae are giant clouds of interstellar gas and dust and are often star-forming regions. This image of the Carina nebula, with our solar system placed in for scale, shows just how massive nebulae can be, often spanning light years across.
Blue Scatter Plots and "r" Scale via Pearson (I made the rest). A Texas Instruments TI-30XIIS can calculate slope and y-intercept for you. Alternatively, there are formulas for each.