<em>From the above options, the best </em><em>Thermal insulator </em><em>will be a </em><em>Plastic cup.</em>
Option (b);
<u>Explanation</u>
Thermal insulators resist to conduct energy or reduction of heat transfer when objects come across in contact with radiation or higher heat object. To conduct energy we need metal or those materials which contain free electrons in it to move from one metal to another.
Plastic doesn't have metallic character so it will resist the heat up to some threshold. Mostly this material is used in separating two current-conducting material. There are many other examples of thermal insulator such as Rubber, fabrics, paper, wood, wool.
Answer:
A molecule is a group of two or more atoms that are held together by chemical bonds.
Explanation:
<u>The troposphere: </u>
H. This layer can have thunderstorms or clear, sunny skies.
A. The biosphere interacts most with this layer.
<u>The stratosphere:</u>
B. It is the second layer from Earth's surface.
G. Winds are strong and steady in this layer.
<u>The mesosphere:</u>
E. It is heated by the ozone layer beneath it.
D. This layer is where most meteor showers occur.
<u>The thermosphere :</u>
F. It contains the ionosphere and exosphere.
C. It contains layers of single, unmixed gas.
<u>Explanation:</u>
Depending on the Earth's temperature the atmosphere can be separated into layers. The troposphere, the stratosphere, the mesosphere and the thermosphere are those layers. The lowest layer is named as Troposphere (0-10 km from the Earth outer surface), it comprises about 75% of the atmosphere's total air and nearly most the water vapor.
Stratosphere (10-30) includes much of the surface ozone. The change in height temperature arises as this ozone absorbs ultraviolet (UV) radiation from the sun. The temperature in Mesosphere (30-50 Km) declines again with height, hitting a minimum of about -90 ° C at the "mesopause." Above this thermosphere (50-400 Km) is settled which is a area where temperatures rise with height once again. The penetration of intense UV and X-ray radiation from the sun induces this temperature rise.
Answer:
8 to 8.5 since that is the recommended and people usualy sleep more than that
Physical change alters a given material without changing its chemical.