<span>LD
means lethal dose. LD50 is the amount of a material, administered at once to
cause the death of half (50%) of a group of test organisms. A test which shows that LD50 of a certain
chemical is 20 mg per kg means that 20 milligrams of that chemical for every 1
kilogram body weight of the test animal when administered in one dose, causes
the death of 50% of the test group.</span>
<span>In order for a climate to be considered "arid", a region/land must have scare rain that does not support the growth of vegetation. It is thought to be an areas that has minimal water sources that cannot produce greenery or other foliage. Arid can be considered extremely dry which will impact the surrounding land's ability to support growing life including plants and other animals.</span>
<span>The correct answer is B. Lack of water. When there's no water and you start to dehydrate, your salivary glands start working extra hard because your mouth can't be dry and the salivary glands produce saliva to keep the mouth and the throat dry. If your throat and mouth are dry you can't even swallow.</span>
Diifer in only one trait.