Classify the statements as correct or incorrect.

a thermometer measures
the average kinetic energy
of a substance.

heat is a form of energy.

heat flows from a colder
substance to a hotter
substance.

convection occurs only
in liquids and gases.

all substances radiate heat.

our body temperature is
always equal to the
temperature around us.

Explanation:

A thermometer does measure the temperature of a body and not the heat. It is known that temperature is a measure of average kinetic energy.

Therefore, the statement a thermometer measures  the average kinetic energy  of a substance is correct.

Heat is a form of energy as it can make a colder substance become hot and it moves from one place to another. Thus, the statement heat is a form of energy is correct. Also, heat flows from hotter substance to colder substance. Hence, the statement heat flows from a colder  substance to a hotter  substance is correct.Convection is a property of fluids or gases which makes less denser (hot) material to rise and more denser (colder) material to sink.

Therefore, the statement convection occurs only  in liquids and gases is correct.

All substances radiate heat is an incorrect statement. For example, a thermos bottle does not radiate heat.Temperature of our body is about 98.4 degree celsius and hence we can conclude that the statement our body temperature is  always equal to the  temperature around us is incorrect.

  concave means having an outline or surface that curves inward like the interior of a circle or sphere. so the mirror curves inward.

Answer sample (c); // would be best because the percentage of the energy in an incident wave that remains in a reflected wave from this material is the smallest;