consider the following products of arbitrary vectors A, B, C, D: 1. A•BXC, 2. (AXB)X(CXD) 3. AXB( C•D), 4. (AXB)•(CXD), 5. A X(BXC). Which of the following is true? write only the Alphabet corresponding to your answer.

Can anybody me with this? ? (picture included.)

Which of the following best describes internal energy? a. the difference between the kinetic and potential energies of the particles in a system b. the sum of the kinetic and potential energies of the particles in a system c. the sum of the kinetic and thermal energies of the particles in a system d. the difference between the kinetic and thermal energies of the particles in a system

Daughter element the new element produced along with a decay particle in a nuclear transmutation 2. half-life the substance that decays in a nuclear transmutation 3. parent element the change of one chemical element into another by nuclear decay or radioactive bombardment 4. transmutation the time required for the decay of one-half of the atoms in a sample of radioactive material