$A$~~$(f(x_1)+f(x_2)+f(x_3)+f(x_4))x$

$=(f(\frac{1}{2})+f(\frac{3}{2})+f(\frac{5}{2})+f(\frac{7}{2}))$

Using $f(x)=x*5^x,$ find the four values $f(\frac{1}{2}),f(\frac{3}{2}),f(\frac{5}{2}),f(\frac{7}{2}).$

$f(\frac{1}{2})=$

$f(\frac{3}{2})=$

$f(\frac{5}{2})=$

$f(\frac{7}{2})=$