Answer:
Radioactive isotopes are unstable and will decay. ... The isotopes will decay into a stable isotope over time. Scientists can tell how old the rock was from looking at the radioactive isotope's half-life, which tells them how long it would take for there to be half the radioactive isotope and half the stable isotope.
Answer:
The ozone layer is a region of high ozone concentration in the stratosphere, 15 to 35 kilometres above Earth's surface. The ozone layer acts as an invisible shield and protects us from harmful ultraviolet (UV) radiation from the sun.
The answer is C because pollution is what traps the "greenhouse gasses"
Answer:
Sa law of demand, habang bumababa ang presyo ng isang kalakal, ang demand para ditto ay tamataas; habang tumataas ang presyo ng isang kalakal, ang dami ng demand ay bumababa – kung ang lahat ng bagay ay mananatiling parehas.
They have different states and so does the U.S.
