Find the values of the following sums. Use formulas for the sum of the first $n$ integers, the first $n$ squares, and the first $n$ cubes as needed to evaluate these sums.

1.    $\displaystyle \sum_{k=1}^{30} \frac{1}{30} =$
   
   
2.    $\displaystyle \sum_{k=1}^{n} \frac{1}{n} =$
   
   
3.    $\displaystyle \sum_{k=1}^{30} \frac{2}{30} =$
   
   
4.    $\displaystyle \sum_{k=1}^{n} \frac{2}{n} =$
   
   
5.    $\displaystyle \sum_{k=1}^{30} \frac{c}{30} =$
   
   
6.    $\displaystyle \sum_{k=1}^{n} \frac{c}{n} =$