Boron-10 has an atomic mass of 10.0129 amu and an abundance of 19.78%. Boron-11 has an atomic mass of 11.0093 amu and is 80.22% abundant. Calculate
the atomic mass of the element Boron (to two decimals).

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C) the increase in atmospheric pressure pushes the walls of the balloon outward thus making it  is the answer.hope i you.

Heat is involved in chemical change in two ways; chemical changes either result in heat being added to or removed from an object, and chemical changes require a certain amount of heat before they can take place.