A green puck with mass 10 kg strikes a stationary yellow puck with mass 10 kg. The green puck was moving at a velocity of 7i – 6j m/s, and its center was at (1, 2) when it hit the yellow puck. Which of the following could be the velocities of the pucks after the collision? (Assume the collision is elastic.)

depends on what you mean by "group." for order, it would be coleoptera (beetles). for class, it would be insecta (insects). for phylum, it would be the arthropoda (animals with jointed exoskeletons).

explanation:

firearm identification is the process of analyzing the bullets and cartridge cases left at a crime scene to determine if they came from a particular firearm. marks on the bullets and cartridges may be common to every firearm of that type. these are called class characteristics.

the answer is the first electromagnet (a). this is because it has more coils around the ferromagnetic material. increasing the number of coils increases the surface area in which the metal interacts with the current in the coil. this enables more atoms in the metal to become aligned hence becoming more magnetized.