Asample of plutonium-239 decays to one-eighth of its original amount after 7.236 x 104 years. what is its half-life?

Which of these metals are magnetic?

Astone is thrown with a speed v0 and returns to earth, as the drawing shows. ignore friction and air resistance, and consider the initial and final locations of the stone. which one of the following correctly describes the change δpe in the gravitational potential energy and the change δke in the kinetic energy of the stone as it moves from its initial to its final location? options a.δpe = 0 j and δke = 0 j b.δpe is positive and δke is negative c.δpe = 0 j and δke is positive d.δpe is negative and δke is positive e.δpe = 0 j and δke is negative

What you see with your eyes is a form of energy. a. light b. heat c. chemical d. electrical