What fraction of carbon-14 remains undecayed after 2,865 years?

This problem has been solved! see the answera non-uniform fire escape ladder is 6.0m long whenextended to the icy alley below. it is held at the top by africtionless pivot, and there is neglibible frictional force fromthe icy surface at the bottom. the ladder weighs 250n, and it'scenter of gravity is 2.0m along the ladder from the bottom. amother and child of total weight 750n are on the ladder 1.5m fromthe pivot. the ladder makes an angle θ with the horizontal.find the magnitude and direction ofa) the force exerted by the icy alley on the ladderb) the force exerted by the ladder on the pivotc) do your answers in part a and b depend on the angle?

During takeoff, the sound intensity level of a jet engine is 170db at a distance of 34 m. what's the sound intensity level at a distance of 1.0 km?

Madison pushes with a 210-n horizontal force on a 24-kg crate of coffee resting on a warehouse floor. the force of friction on the crate is 74 n. what is the acceleration?