Срочно нужна помощь

1. $\sqrt{242} = \sqrt{2*121} = \sqrt{2} * \sqrt{121} =11 \sqrt{2}$
$\sqrt{2 \frac{39}{125} } = \sqrt{\frac{289}{125} } = \sqrt{289} * \sqrt{ \frac{1}{25*5} } = 17* \frac{1}{5} \sqrt{ \frac{1}{5} } = \frac{17}{5} \sqrt{ \frac{1}{5} }$
$\sqrt{50x} = \sqrt{25*2*x} =5 \sqrt{2x}$
$\sqrt{196x^4y^5} = \sqrt{196} * \sqrt{x^4}* \sqrt{y^5} =14x^2* \sqrt{y^4*y} =14x^2y^2 \sqrt{y}$
2. $4 \sqrt{6} = \sqrt{4^2*6} = \sqrt{16*6} = \sqrt{96}$
$-5 \sqrt{10} = - \sqrt{5^2*10} =- \sqrt{250}$
$7b \sqrt{b} = \sqrt{7^2b^2*b } = \sqrt{49b^3}$
$5y^4 \sqrt{ \frac{2y}{5} } = \sqrt{5^2(y^4)^2* \frac{2y}{5} } = \sqrt{25y^8* \frac{2y}{5} } = \sqrt{ \frac{50y^9}{5} } = \sqrt{10y^9}$
3. $M = \frac{1}{3} ^2 *( \sqrt{32} )^2 = \frac{1}{9} *32 = \frac{32}{9}$ ≈ 3,55
$N = \frac{1}{5} ^2*( \sqrt{72} )^2 = \frac{1}{25} *72 = \frac{72}{25} = 2,88$
очевидно, M>N