Halogens combine with most metals to form _ such as _

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.

What best discribes the relationship between wavelength and frequency in a electromagnetic wave

Answer asap : ( a. how does mucus prevent the entry of pathogens? b. describe two ways white blood cells protect us from pathogens.