What is the difference between a craton, sheild, and platform?

Which of the following can occur to two segments of a population if they are geographically isolated 1.) they can only share some types of genes 2.)both groups most likely become extinct 3.)they find a way to come back together 4.)eventually they become separate species

The united states uses which source of energy to produce almost 40 percent of its electricity

Why can cancer in the lymph nodes (lymphoma) be particularly dangerous? a. the lymph node's ability to produce cancer-fighting lymphocytes would be compromised. b. the lymph node's ability to produce cancer-fighting lymph would be compromised. c. the lymph nodes produce lymph, which nourishes growing cancer cells. d. the lymph nodes produce chyle, which nourishes growing cancer cells.