Which statement most accurately compares the temperature of the core of the sun to its surface?
a) the core is more than a thousand times hotter than the surface
b) the surface is more than a thousand times hotter than the core
c) the core is more than a million times hotter than the surface
d) the surface is more than a million times hotter than the core

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

the mantle

explanation:

earth is divided into three layers: the crust or the outermost layer on which we live; the underlying, middle layer - the mantle - and the core (the innermost layer of earth).