What is radioactivity?

A. The movement of electrons around an atomic nucleus

B. The emission of high-energy particles or waves from atoms

C. A term that describes the forces that hold atomic nuclei
together

D. The application of heat energy to an atomic nucleus

Curious carl calculated the density of a cube to be 4.50 g/cm3. what is the density of the cube in g/l?

The boy of mass 30 kg is at r1= 2 meters from the fulcrum. of the girl is 45 kg, at what r2 must she sit so that they are balanced ?

Assume you measured the mass of the cart to be (500 ± 1) g and the mass of the additional mass you put on the cart to be (500 ± 1) g as well. since the scale you are using in the lab cannot measure objects heavier than 600g you will have to sum up individual pieces and propagate the error. so what would be the mass and the standard error of the cart and the mass