What is the half-life of an isotope that decays to 25% of its original activity in 70.8 hours?

Explain how the meanings of the terms habitat and niche differ?

How can an experiment support or fail to support a hypothesis?

When one bumper car hits another, how does the reaction force affect the first car? a. The car moves in the direction opposite of the action force. b. The car comes to a stop. c. The car moves in the same direction as the action force.

Which of the following has the greatest magnitude? 1 Newton 10 Newtons 30 Newtons

Which of the following elements are non-reactive because their outer electron energy levels are full? A. Aluminum B. Carbon C. Krypton D. Uranium

The force exerted by the wind on the sails of a sailboat is fsail = 410 n north. the water exerts a force of fkeel = 200 n east. if the boat (including its crew) has a mass of 300 kg, what are the magnitude and direction of its acceleration?

How much energy would be released if we could completely convert the mass of a 4.50 kilogram rock into energy? Joules One "megaton" is the amount of energy released by the detonation of 1 million tons of dynamite. One megaton is equal to 4.

suppose a rock on Earth is dropped in a vacuum and has initial speed of 0 m/s. what is the rock's speed after 2 seconds, in m/s, if it encounters no air resistance

The antiseptics used for cuts and wounds in human flesh have low surface tension. Why?

What affects the amount of potential energy stored in the magnetic field when a magnet is moved against a magnetic force?