What structure is the opening that allows you to enter the eye

How will the emission of an alpha particle affect the atomic number of an atom

How do you identify the anode on a power source such as a battery? how do you identify the cathode? how are terms anion and cation?

Two metal blocks that have slightly different temperatures are placed next to one another. after five minutes, they both have lower but equal temperatures. according to the law of conservation of energy, what  most likelyhappened? energy was created inside the blocks. energy was destroyed inside the blocks. energy was absorbed into the blocks from outside the system. energy was transferred from the warmer block to the cooler block.