I think observation and measurable.
D,record observations and measurements.
Answer:
The options are unclear but the answer is 8^2π square feet or 64π sqfeet
Explanation:
Area of a circle is denoted by: πr^2 where r is the radius of the circle.
In this question, the diameter was given. The diameter of a circle is twice the radius. Therefore, in order to get the radius, we divide the diameter by 2 i.e. r = d/2
= 16/2 = 8 feet.
Thus, the radius = 8 feet.
Hence, Area of a circle = πr^2
= π × 8^2
= 64π or 8^2π sqfeet.
Okay. The destruction of tundra vegetation will not really freeze the soil or deepen the active zone much. Therefore, A and C are eliminated. The destruction of the vegetation can actually melt permafrost, which contributes to global warming. The answer is D.