In the picture below the igneous intrusion (V) was examined and scientists found that this rock had about 25% of the overall Uranium 235 left in the composition of the rock. This fact helps scientists determine how old the intrusion is and in turn will give clues about the age of the rock layers around and beneath the intrusion. Using the amount of Uranium 235 left in the intrusion how old is the intrusion?

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