posted by Rachel .
The heat of volcanoes and hot springs comes from trace amounts of radioactive minerals found in the Earth's interior. Why isn't the same rock at the Earth's surface warm?
From Britannica Online:
Hot springs and geysers also are manifestations of volcanic activity. They result from the interaction of groundwater with magma or with solidified but still-hot igneous rocks at shallow depths.
A microwave oven has a power requirement of 1248 W. A frozen dinner requires 4.1 min to heat on full power. How much electrical energy (in kWh) is used?