today is my parents anniversary what gift should I give them I can't decide we are going to celebrate this evening pls help

The gun from the crime scene shows tool marks where the serial numbers are ground off. there are also tool marks on the bullets left behind. what information can the tool marks on the bullets and gun provide about the crime? what type of evidence does this information provide, individual or class?

Explain how a step-down transformer makes electricity safe for use in homes

What caused magnetic fields? what happens if you keep breaking a magnet in two until you reach a single atom?