HELP 50 PTS! A student wants to conduct a science fair project about why plants move in response to light. His teacher tells him that he should use repeated trials in his experiment Why should the student use repetition in his experiment? to provide him with results from a group with which to compare the experimental treatment to allow his classmates to conduct the same experiment to confirm his results to ensure that his experimental results are accurate and the experiment did not contain flaws to practice the procedure for conducting scientific experiments

Idont know. if you want an answer you need to give us some context dude.

I'm sorry but i'm only grade

Answerthis solution will not form a precipitateexplanationsolubility equilbrium:         pbf₂(s)  ⇄ pb²⁺(aq) + 2 f⁻(aq)the solubility product expression is    (we exclude solids from the equilibrium expression).now suppose we have the trial ion product q, which we can define as    then, we can interpret  q as the product of the concentration of the ions that we have and ksp as the product of the ion concentrations that are needed to form a saturated solution.if q > ksp, then that implies that there will be a surplus of ions that exceed the amount that is required to form a saturated solution. a precipitate will then form (the precipitate continually  forms until the surplus ions are removed and q is decreased to ksp's value).if q = ksp, the saturated solution that forms is barely saturated and the precipitate will be minimal.if q < ksp, then the ion concentration will not be enough to form a saturated solution (so no precipitate).using our information, we calculate the trial ion product:     since q = 2.7  × 10⁻⁸ < ksp =  4  ×  10⁻⁸, a precipitate will not form.

Hcn is your answer my guy : )