Answer:
D. A brown gas produced
Explanation:
When a chemical reaction occur, there are several changes that takes place such as change in color, odor change, formation of a gas, and formation of a precipitate etcetera.
In the given chemical reaction, two colorless gas (NO and O2) react together and form brown gas (NO2). So, the change of gas from colorless to brown gas is the evidence that shows chemical reaction occurred.
Hence, the correct option is "D. A brown gas produced".
Answer:
The answer is: Classical Conditioning.
Explanation:
- According to the theory of Classical Conditioning, an Unconditional Stimulus can be defined as such a stimulus that is capable of triggering a response spontaneously and naturally without the requirement of a previous learning or knowledge about the stimulus.
- A Neutral stimulus can be defined as such a stimulus which is responsible for drawing or focusing the attention of a person to a particular event.
- A Conditional Stimulus can be defined as such a stimulus which is generated due to the repeated integration of an Unconditional stimulus to a Neutral stimulus. The repeated integration eventually results in the generation of a conditioned response.
- In the given example, a bit of black pepper blown into the eyes for the first time is an example of unconditional stimulus. This stimulus initiates a spontaneous or unconditional response, that is, blinking of eyes.
- But, when this unconditional stimulus gets integrated to the neutral stimulus (irritation in the eyes draws the attention of the person) repeatedly, it can result in the generation of a Conditioned Response (blinking of eyes whenever any foreign object gets into it).
The first cell that was viewed by the light microscope was the oak bark.
Answer:
The four seasons happen because of the tilt of the Earth's axis. At different times of the year, the sun's rays hit different parts of the globe more directly. The angle of the Earth's axis tilts the Northern Hemisphere towards the sun during the summer.
Explanation:
Water, soil, sunlight, H20, and nutrients.
