Bereken:

$6,5\times8\ -\ 8\times1,5=$

$6,5\ \times\left(8\ -\ 8\right)\ \times1,5=$

$2\times3\ -\ \frac{5}{\left(3-1\right)}=$

$7\ +\ 3\times5^2=$

$\sqrt{49}+5\times\frac{4}{20}=$