D) Vaporization; Perspiration
Perspiration is when the body sweats the sweat evaporates and cools down the body
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.
1) Speed = distance / time
s = 60 / 2
s = 30 km/h
In short, Your Answer would be Option B
2) Speed = distance / time
s = 25/4
s = 6.25 km/h
In short, Your Answer would be Option B
[ Direction not needed as it is speed not velocity ]
Hope this helps!
Answer:
Humans have breached this cycle by digging up fossil fuels and burning them, leading to carbon dioxide building up in the atmosphere faster than natural systems can soak it up. This has led to a net increase in greenhouse gases in the atmosphere, causing the planet to heat up.
Explanation: