Crossword puzzle clue "me first problem"

First word across in the first-ever crossword (1913) and the first of a dozen appearances of the word in this puzzle's grid, written word search-style (left, right, down, and diagonally) ... Can you f

"Me first" problem

Certain "First World problem"

"Fancy" singer featured on "Problem" who in 2014 became the second ever to be simultaneously #1 and #2 with her first two hits: 2 wds.

First number in a subtraction problem

Addition problem for a first-grader