Reformat text surrounding Latex equation in "Challenge problems"

Author: kakirastern

tutorials/notebooks/units-and-integration/units-and-integration.ipynb

@@ -326,7 +326,11 @@
     "\n",
     "* Right now, we aren't worried about the bounds of the power law, but the IMF should drop off to zero probability at masses below .01 solar masses and above 100 solar masses. Modify `PowerLawPDF` in a way that allows both `float` and `numpy.ndarray` inputs.\n",
     "* Modify the `PowerLawPDF` class to explicitly use `astropy`'s `units` constructs.\n",
-    "* Derive a relationship between recent star-formation rate and $H\\alpha$ luminosity. In other words, for the function $${\\rm SFR \\, [\\frac{M_{\\odot}}{yr}]} = {\\rm C \\, L_{H\\alpha} \\, [\\frac{erg}{s}]} \\, ,$$ find a value of $C$. How does this depend on the slope and endpoints of the IMF?\n",
+    "* Derive a relationship between recent star-formation rate and $H\\alpha$ luminosity. In other words, for the function\n",
+    "\n",
+    "$${\\rm SFR \\, [\\frac{M_{\\odot}}{yr}]} = {\\rm C \\, L_{H\\alpha} \\, [\\frac{erg}{s}]} \\, ,$$\n",
+    "\n",
+    " * find a value of $C$. How does this depend on the slope and endpoints of the IMF?\n",
     " * take a look at Appendix B of [Hunter & Elmegreen 2004, AJ, 128, 2170](http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:astro-ph/0408229)\n",
     " * what effect does changing the power-law index or upper mass limit of the IMF have on the value of $C$?\n",
     " * predict the effect on the value of $C$ of using a different form of the IMF, like Kroupa or Chabrier (both are lighter on the low-mass end). If you're not tired of IMFs yet, try defining a new class that implements a broken-power-law (Kroupa) or log-parabola (Chabrier) IMF. Perform the same calculations as above."