Classify each expression as monomial, binomial, trinomial or polynomial. ___________1.) 2xy
_______________2.) 5c + d – 1
___________3.) 2xyz + 3x _______________4.) yxzabc2 ___________5.) 9
_______________6.) a2 – ab3c + abc ___________7.) x2 + 3x4 _______________8.) 1 – x + x2 ___________9.) 5a + b + c ______________10.) 5z – 7 ​