It is <span>c. they're convenient.
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Answer:
The oblique illumination is
used by the microscopists to resolve N. Spencrii in the Dark Field Condensers.
Explanation:
It was found that the use of oblique light was required to resolve the striae. Oblique illumination was the first step toward dark field microscopy. In dark field, light
seems to radiate from the specimen while all the rest of the field is black. Resolution is as good as that in bright field while contrast is enhanced.
In dark field microscopy, no
direct light from the condenser enters the objective lens. Only light
that is reflected, refracted or diffracted by the specimen enters the objective. The dark field condenser produces a circle of light. The
light is at an extremely oblique angle to the surface of the slide. This
oblique light comes to a focus on the specimen. It then diverges so
strongly that no direct light enters the objective. This type
of illumination is a hollow cone of light.
Answer: the length property
Explanation:
The History object contains a single property, the length property, which contains the specific number of documents that have been opened during the current browser session. The length property of the History object specifies the number of elements in the browsing history list, The number of pages in history can be found by accessing the history object's length property.
Answer: a. Discharged, untreated, into surface waters.
Explanation:
Most of the waste water and sewage water is left untreated into the surrounding soil or water which is the main cause of pollution. Due to lack of drainage system or septic chemical treatment the sewage water drain from major cities is discharged into the surface water untreated. This water can deteriorate the quality of portable water and can affect the population of many aquatic species reducing the aquatic biodiversity. The sewage discharge consists of nitrogen and phosphorus like minerals which can result in algal bloom causing eutrophication.
