Why can some electric appliances be immersed in water without damage

What are the primary responsibilities of a chemical engineer involved in "r& d"? develop large scale manufacturing operations discover new products and processes training of new chemists determine products needed by consumers

Why does the sun appear to be the brightest star in the sky? a- its apparent brightness is much greater than other stars. b- it burns more gas, making it brighter than any other star. c- it is the largest star in the galaxy, so it is the brightest star. d- its relative distance to earth is closer than the other stars.

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