2. Two boxes stacked on top of one another weigh 100 kg total. They apply a friction force of 250N. You apply a force of 300N in the right direction.
What is the total net force and direction of the box?

false br

i think its c if i'm wrong

3. dark matter

empty space could also be a simple vacuum

no. bullets are macro objects. wave nature is for light waves, extremely tiny particles. if a light particle was the size of your finger, the bullet would be the size of the universe. so basically, that huge difference in size makes the wave nature of matter insignificant.