Решите пожалуйста, заранее спасибо!

1) $\frac{5}{m} + \frac{2}{ m^{3} } = \frac{5 m^{2}+ 2 }{ m^{3} }$
2) $\frac{y+2}{7y} - \frac{2x - 1}{14x} = \frac{2xy + 4x- 2xy+ y}{14xy} = \frac{4x + y}{14xy}$
3) $\frac{6mn}{9 m^{4} } - \frac{2m + n}{3m ^{3} } = \frac{6mn - 6 m^{2}- 3mn }{9 m^{4} } = \frac{3mn - 6 m^{2} }{9 m^{4} } = \frac{3m(n - 2m)}{9 m^{4} } = \frac{n - 2m}{3 m^{3} }$
4) $4y - \frac{2 - 3 y^{2} }{3y} = \frac{12 y^{2}- 2 + 3 y^{2} }{3y} = \frac{15 y^{2}- 2 }{3y}$
$2x - \frac{x + 3y}{6} + \frac{x - 2y}{3} = \frac{12x- x - 3y + 2x - 4y}{6} = \frac{13x - 7y}{6}$