A book is resting on the floor. It has 25 J of energy. A student lifts the book and places it on the top shelf of a bookshelf. The student uses 200 J of energy to lift the book onto the shelf. How much energy does the book have at the top of the shelf? A. Exactly 25 J
B. About 225 J
C. At least250 J
D. Negative 175 J PLSS QUICK (3 minutes at most) ILL GIVE 70 POINTS AND BRAINLIEST (FOR CORRECT ANSWER)

Zirconium has an hcp crystal structure and a density of 6.51 g/cm3. (a) what is the volume of its unit cell in m3? (b) if the c/a ratio is 1.593, compute the values of c and a.

Exercise 2. find the wavelength of a photon emitted when an electron jumps from the n = 3 energy level down to the n = 2 energy level. where is this photon in the electromagnetic spectrum?

On a horizontal frictionless surface, a small block with mass 0.200 kg has a collision with a block of mass 0.400 kg. immediately after the collision, the 0.200 kg block is moving at 12.0 m/s in the direction 30° north of east and the 0.400 kg block is moving at 11.2 m/s in the direction 53.1° south of east. use coordinates where the +x-axis is east and the +y-axis is north.(a) what is the total kinetic energy of the two blocks after the collision (in ) what is the x-component of the total momentum of the two blocks after the collision? (indicate the direction with the sign of your ) what is the y-component of the total momentum of the two blocks after the collision? (indicate the direction with the sign of your answer.)