Answer :
[tex]Formula\ for\ heat\ energy:\\\\
Q=mCp(T_2-T_1)\\\\
m-mass=0,1kg\\Cp-specific\ heat\ of\ glass=800\frac{J}{kgC^{\circ}}\\T_2=15^{\circ}\\T_1=-45^{\circ}\\\\
Q=0,1*800(15+45)=80*60=4800J\\\\4800J\ is\ required\ to\ heat\ this\ glass.[/tex]