What's mass?
a. the sum of the number of protons and neutrons in an atom
b. the force that gravity exerts upon an object
oc. a measure of an element's attraction for electrons
d. a measure of the amount of matter an object contains

your the dumbest b**tch ive ever seen

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explanation:

b r

he may like cookies

they had the law tat factories that produces smoke cannot be built near residential buildings.

building of proper sewage system was done to ensure that the waste is carried away from the humans so that they do not get diseases from it.

also they built water systems to provide water in those areas which are drought prone.

the nitrogen cycle provides nitrogen to the ecosystem from the atmosphere, ground and oceans. nitrogen is an important component of complex molecules such as amino acids and nucleotides, which lead to the creation of proteins and dna, the building blocks of all life. plants absorb nitrogen in the form of ammonium, nitrate ion and, on rare occasions, as amino acids. animals receive nitrogen necessary for biological processes from feeding on living or dead organic matter.