How many joules does it take to heat up 15.1 kg of glass from 15°c to 45°c

380,520 Joules

That is;

Q = m×c×Δt

In the question above;

Mass of glass is 15.1 kg

Change in temperature = 45°C - 15 °C

                                       = 30°C

Specific heat capacity of glass = 840 J/kg/°C

Therefore;

Quantity of heat, Q = 15.1 kg × 840 J/kg/°C × 30°C

                               = 380,520 Joules

Hence, it takes 380,520 Joules to heat up 15.1 kg of glass from 15°C to 45°C.