Which form of decay produces a nucleus similar to the element helium? alpha particle

beta particle

gamma ray

Gymnast always perform on padded mats. how does the mats protect the gymnast

2pos suppose an object in free fall is dropped from a building. its starting velocity is 0 m/s. ignoring the effects of air resistance, what is the speed (in m/s) of the object after falling 3 seconds? give your answer as a positive decimal without units. answer here

Which of the following units is not an official si unit? mole liter kilogram ampere