Asample of radium-226 will decay to ¼ of its original amount after 3200 years. what is the half-life of radium-226?

years?

In a stagnant pool of water, a crayfish may spend much of its time lying with one side of its carapace near the surface of the water. in this position, it will move the walking legs on that side in a rhythmic back-and-forth motion. explain the likely function of this behavior.