What is the like term for 4m + (-3n) + n? What is the like term for c+2c+c-5c+1

a) The three terms have variables m, n, n. The two like terms are the last two terms, which both have variable n: - 3n, n.

b) The 5 terms have variables c, c, c, c, -. The like terms are the first four, which all have variable c: c, 2c, c, - 5c.