A student is doing a genetics experiment on beetles. The student breeds a pure green beetle with a pure brown beetle. The student repeats this experiment ten more times. Every time the student performs this cross, all of the offspring are green. What does that mean? A. The gene for green and brown are equally expressed because half the beetle parents have a green phenotype and half the beetle parents have a brown phenotype. B. The gene for green color is dominant over the gene for brown because all the beetle offspring have a brown phenotype. C. The gene for brown color is dominant over the gene for green color because all of the beetle offspring have a brown genotype. D. The gene for green color is dominant over the gene for brown color because all the beetle offspring have a green phenotype.

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.

answer( sicar );