The thick layer is the-crust
Electromagntic wave, such as an X-ray.
Explanation:
- Electromagnetic wave does not require any medium to travel. These waves propagate outwards from the source.
- They can travel even through the vacuum of outer space.
- The major source is the sun which emits radiation in the form of the Electromagnetic spectrum.
- These waves travel through oscillating electrical and magnetic fields generated by the oscillating charged particles.
- These waves oscillate in the perpendicular direction of planes concerning each other and are in form.
- Electromagnetic waves travel at speed of light.
Answer: b. Clear-cutting
Explanation: Clear cutting is a cheap and effective way of harvesting trees or timbers, this methods helps the forest operators to get the best out of a forest at a very reduced cost.
Clear-cutting is bad because removing the whole tree from an area destroys outrightly the natural habitat of most widelife, and it will also lead to the destruction of the eco-system that relies on the forest.
Advantage: #1 Almost 0 emissions (very low greenhouse gas emissions).
#2 They can be sited almost anywhere unlike oil which is mostly imported
Disadvantage #1 Nuclear plants are more expensive to build and maintain.
#2 Proliferation concerns - breeder reactors yield products that could potentially be stolen and turned into an atomic weapon
APEC later added SECURITY AND TERRORISM to their agenda. APEC is a forum that is made up of twenty one member countries that was established in 1989.Their principal objective is to promote free trade throughout the Asia - Pacific region. Later on, APEC added security and terrorism to the list of their major objectives.