On a line graph, a flat, horizontal line means a. that the y variable is increasing. b. the y variable is leveling off in order to get to a decrease. c. there is a positive relationship between the two variables. d. that the y variable is staying the same.

Cancer cells spread to other parts of the body by entering the bloodstream. which of the following organs could prevent a cancer cell in the bloodstream from spreading, and why? a. the spleen, because it releases lymphocytes into the blood b. the peyer's patches, because they release lymphocytes into the blood c. the lymph nodes, because they release lymph into the blood d. the thymus, because it releases lymph into the blood