Which classification of bones is described as having complex shapes, with varied internal structure?

Modern whales developed their traits through natural selection what occurs during the process of natural selection

Many organizations release indexes used to measure the development of the world's countries. as we learned in this lesson, these indexes measure many factors, from life expectancy to happiness. in your opinion, what are the three most important factors we can use to determine how developed a country might be? explain your answers in a few sentences.

What two conditions must be present for osmosis to occur?