The propagation velocity of the waves depends on density and elasticity of the medium. Velocity tends to increase with depth and ranges from approximately 2 to 8 km/s in the Earth's crust up to 13 km/s in the deep mantle.
Discretionary calories are overabundance calories to appreciate once your necessary supplement needs are met. They can be utilized toward higher-fat types of nourishments like milk, cheddar and meat, and high-fat and sugary fixings, for example, margarine, sauce, sugar, and syrup. Discretionary calories can likewise tally toward pop, treats, and liquor
On the off chance that none of these nourishments sound alluring, they can even be utilized for extra servings of your preferred solid food sources
