8. Definite Integrals

Evaluate the following summation: 

$\sum_{i=1}^4i^2-3i+8$

Evaluate the following summation: 

$\sum_{k=1}^4\left(\frac{k}{_{}2}\right)^2$

Evaluate the following summation: 

$\sum_{i=0}^2\frac{2i}{3}$

Evaluate the following summation: 

$\sum_{t=2}^65t+\frac{4}{t}$