I think the answer is a because it is losing mass do to it melting not completely sure tho
A radioactive element is an element which is subject to spontaneous degeneration of its nucleus followed by the emission of alpha, beta and gamma particles. All elements with atomic numbers greater than 83 are radioactive.
The given phrases that describe radioactive elements are-
They have a consistent number of particles
- the particles are alpha, beta and gamma particles.
They have a half-life that determines their rate of decay.
Explanation for other options:
Not all elements occur in nature. Radioactive decay rates may not be constant as the decay happens when a radioactive substance emits a particle. It is not possible to predict exactly when a given atom of a substance will emit a particular particle. When the radioactive element release energy and particles, it decays.
The Tower Karst <span>represents the most advanced stage of erosion.</span>
Each cell is alive even if it is part of a multi celled body, and all living organisms consist of one or more cells. Also, cells reproduce by dividing so it follows that all existing cells must have arisen by division of other cells. As a cell divides it passes it hereditary material- its DNA- to offspring.