Ducjuliu42 uvuleearth space science /19. britten baker 4932 siquestion 3(multiple choice worth 2 points)[bws.02]two students completed an experiment to determine if pesticide use at local farms was causing fish kills in a local pond. thesteps of the experiment are listed below.1. select different locations to collect water samples in the pond.2. collect a 5-ml water sample at 8 am at a different location each day for 10 days.3. measure the amount of pesticide present in each sample using the same measurement tools. after analyzing their data, the students conclude that pesticide runoff from farms is not causing the fish to die in the pond. whichof these statements best describes why their conclusion is not valid? the amount of water collected each day was the independent variable. the daily location for sample collection was not a controlled variable. pesticide measurements were the dependent variable. the time of sample collection was not a controlled variable. nexomquestion 1 (answered)previous question

russian is not my first language, so i'm afraid i can't write out an answer in russian, but hopefully you can find a way to do so. here's my best translation of the problem: you're given a plot of a particle's position in one-dimensional space over time, and you're asked to find either the total distance traveled by the particle after 6 seconds had elapsed, or the total displacement of the particle after 6 seconds.

if you want the total distance traveled, you would first need to determine the particle's velocity as a function of time, then integrate that over the 6-second interval. we know the position function is quadratic with roots at 0 and 6, so we have

where is unknown. because the position is parabolic, there is symmetry about the midpoint at , and we know that

so that the position function is

which means the velocity is

then the total distance traveled is

so the total distance traveled is 20 m.

on the other hand, if you want to find displacement: the particle starts at and ends at , so its displacement is 0.