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Which is the first incorrect step in the solution shown above?​

(6.03) what is the constant term in the expression 6x3y + 7x2 + 5x + 4? (input a numeric value only.) numerical answers expected! me pls! fast pls

Question part points submissions used suppose that 100 lottery tickets are given out in sequence to the first 100 guests to arrive at a party. of these 100 tickets, only 12 are winning tickets. the generalized pigeonhole principle guarantees that there must be a streak of at least l losing tickets in a row. find l.

Which expressions are equivalent to k/2 choose 2 answers: a k-2 b 2/k c 1/2k d k/2 e k+k