The answer is D. Small object made of ice and dust that orbits the Sun and forms a coma as it approaches the Sun.
Answer:
Autotrophs
Explanation:
When you go down a food chain continuing to ask "what does it eat?" the last living thing that you will land upon is an autotroph.
Autotrophs are the primary producers as they (photoautotrophs) use the energy either from the sun to prepare there food by the process of photosynthesis or, more rarely, obtain chemical energy through oxidation (chemoautotrophs) to make organic substances from inorganic ones.
Autotrophs get consumed by the primary consumers in the food chain.
is the intensity of the sound.
Answer: Option B
<u>Explanation:</u>
The range of sound intensity that people can recognize is so large (including 13 magnitude levels). The intensity of the weakest audible noise is called the hearing threshold. (intensity about
). Because it is difficult to imagine numbers in such a large range, it is advisable to use a scale from 0 to 100.
This is the goal of the decibel scale (dB). Because logarithm has the property of recording a large number and returning a small number, the dB scale is based on a logarithmic scale. The scale is defined so that the hearing threshold has intensity level of sound as 0.

Where,
I = Intensity of the sound produced
= Standard Intensity of sound of 60 decibels = 
So for 19 decibels, determine I as follows,



When log goes to other side, express in 10 to the power of that side value,


Answer:
Required energy Q = 231 J
Explanation:
Given:
Specific heat of copper C = 0.385 J/g°C
Mass m = 20 g
ΔT = (50 - 20)°C = 30 °C
Find:
Required energy
Computation:
Q = mCΔT
Q = 20(0.385)(30)
Required energy Q = 231 J