Which term describes the time it takes for half of a radioactive elements atoms to decay? absolute age half-life radioactive decay relative age

Water at room temperature of 20.0°c is poured into an aluminum cylinder which has graduation markings etched on the inside. the reading in the graduations is 300.0 cc. the cylinder with the water in it is then immersed in a constant temperature bath at a temperature of 100°c. what is the reading for the level of water on the graduations of the cylinder after the water and the cylinder reach thermal equilibrium with the bath? the volume coefficient of expansion of water is 2.07 x 10^-4 k-1, and the linear coefficient of expansion of aluminum is 23.0 x 10^-6 k-1. a) 305.0 cc b) 304.0 cc c) 303.5 cc d) 303.3 cc e) 304.5 cc

The speed of light in a material is 0.50 c. what is the critical angle of a light ray at the interface between the material and a vacuum?

If the wheels lock when braking suddenly the vehicle: a: loses traction b: lose steering wheel ability c: gain speed slightly d: gain steering ability