! which of the following has stored gravitational potential energy?

a. a mouse eating cheese
b. a leaf hanging on a tree
c. a lightbulb burning
d. a car sitting in a driveway

In this synthesis reaction what products will form

What element breaks down into yttrium-90?

Astudent carefully transfers 30 g of water and 30 g of alcohol in a glass tube, forming two layers and filling the tube completely. after sealing the tube, the student mixes the solutions, and notices a bubble that forms in the tube. what is the mass of the contents in the glass tube after mixing?