Выберите пары подобных одночленов.

• \(5x^2y\) и \(-2xyx\)
• \(x^2yx^2\) и \(6x^2y\)
• \(-7a^2b^2a^3\) и \(-2ab^2a^4\)
• \(6mn\) и \(6m^2n\)
• \(3mn^5kn\) и \(-2nmn^3kn\)
• \(c^2d\) и \(d^2c\)