What is scalar quantity ?

physics, scalars are physical quantities that are unaffected by changes to a vector space basis. Scalars are often accompanied by units of measurement, as in "10 cm".

they physical quantities that are uneffected by changes to a vector space basis

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current

fe 55.85 g/mol and h2o 18.02 g/mol.