What are the different forms of same element with different molecular structures?

If jerome is swinging on a rope and transferring energy from gravitational potential energy to kinetic energy, is being done.

An object with initial temperature 130 ∘ f is submerged in large tank of water whose temperature is 50 ∘ f . find a formula for f ( t ) , the temperature of the object after t minutes, if the cooling constant is k = − 0.2 . remember newton's law of cooling (the rate of change of temperature with respect to time is equal to k times the difference between the temperature of the object and the surrounding temperature) ! : )

Why is the use of carbon-14 limited