The independent variable something that you cannot control...But the dependent variable is what you can control. For the first question, the number of seeds is a dependent variable and quality of the plant is the independent variable. A constant would be the type of flower l, that stays the same.
Number two: IV is coordination, and DV is amount of sleep. A constant would be the agility tasks. Your hypothesis could be that if your alarm is 7 a.m. you will better coordination than the people that have alarms set for 4 a.m..
Number Three: I can't see number three very well.
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