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42,52,55,56,57

42) 76

b)70

Explanation:

52) because you don't want to confuse different units. one ex)1cm is 1/ 100 of a meter

55) 1 km=1,000 meters

b) 10 decimterers = 1 meter

56)The SI standard for length is the meter the standard for volume is the cubic decimeter

ex) 1cm³=1mL

57) The two scales are the same. but there are no negative temperatures in Kelvin. 0 Kelvin is the lowest temperature possible.

0 Kelvin= -274.5 Celsius

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.