A roller coaster at an amusement park has a dip that bottoms out in a vertical circle of radius . A passenger feels the seat of the car pushing upward on her with a force equal to twice her weight as she goes through the dip. If , how fast is the roller coaster traveling at the bottom of the dip

Zeros that follow non-zeros numbers and are also to the right of a decimal point are significant

What elements are found in the inner and out core of the earth? the correct layers of earth's interior from the top to the center? what is the unwanted material that is removed from a mine called? how much stronger is an earthquake that registers 5 on the richter as opposed to 2? what occurs at a convergence plate boundary? the majority of the the earth's rock what is the most common element found in the earth's crust? what element is found in pyrite that contributes to acid mine drainage? why must mining companies post bond prior to permitting? how are bacteria being used in treating effluent from mines? what is a problem of acid mine drainage in rivers and soils? what do tectonic plates move on? why is gold smelting so damaging? how are artesian wells formed? where is dammed water colder than the river it flows into? what is one of the problems of uncontained aqueducts? what is the largest use of industrial water? underground sand and gravel formations that can store water? what type of water test measure acidity? which type of water test for cloudiness from suspended solids? what water test measures the amount of calcium and magnesium? these are all problems of coal power plants all of the following are advantages of riparian lands along rivers what type of water would be the warmest and have the least amount of dissolved oxygen? the zone of aeration is

An object weigh 40n in air ,weigh 20n when submerged in water, and 30n when submerged in a liquid of unknown liquid density. what is the density of unknown of liquid?