Asolution should in order to prevent water gain or loss in a substance
1)hypotonic
2)hypertonic
3)isotonic

white blood cells or wbc s are mainly 2 types-

1.agranulocytes

2.granulocytes

the monocytes or macrophages of agranulocytes , dendritic cells which are accessory leucocytes, and b cells which is one type of lymphocytes   identify the antigens present on the pathogen's surface. these three cells are called antigen presenting cells(apc) which are phagocytes and destroy the antigens by secreting antitoxins. besides this leukocyte is always plays vital role in the immunity of the body.

a=c and then d= c because of the band so you get ac/dc and you add them together you get sound waves