Please help with this question i will give brain-liest to the first one who helps.

What's the waste product of electrons and pyruvate combining in fermentation?  

Which of the following describes the difference in stimuli required to detect a difference between the stimuli? a. just noticeableb. signal detectionc. subliminald. top down

Some plants have reproductive structures that them reproduce using natural forces or animals. how does the reproductive structure shown here ensure the reproductive success of plants?