Distinguish between naturally and artificially acquired active immunity and give an example of each.

all matter is made up of atoms

in any element all atoms are the same

elements in a compound are always in a constant ratio: apex

b tumor cells have a cell wall instead of a membrane

explanation:

tumor cells different from normal cells because tumor cells have a cell wall instead of a membrane.

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.