fix(2019-fall-midterm): fix typo (#34)

* fix(2019-fall-midterm): fix typo

* fix: remove unnecessary headers

src/content/questions/comp2804/2019-fall-midterm/1/solution.md

@@ -1,9 +1,5 @@
-1. Determine pombinations
+We choose 1 of the $f$ girls to be the president: $\binom{f}{1}=f$
 
-   We choose 1 of the $f$ girls to be the president: $\binom{f}{1}=f$
+We choose 3 of the remaining $f-1$ girls and m guys to be vice presidents: $\binom{f-1+m}{3}$
 
-   We choose 3 of the remaining $f-1$ girls and m guys to be vice presidents: $\binom{f-1+m}{3}$
-
-2. Profit
-
-   Thus, the total number of ways to choose the president and vice presidents is $f \cdot \binom{f-1+m}{3}$
+Thus, the total number of ways to choose the president and vice presidents is $f \cdot \binom{f-1+m}{3}$