D. Fossil fuels are the remnants of organisms that lived a long time ago and were buried, heated, and formed into hydrocarbons.
The causes of monocultures are the economics of
global product of agriculture, standard of industrial society, and the apparent
“simplicity” of managing only one crop.
The major cause of the loss of top soil is
soil erosion (which is caused by the factors like water, wind and tillage of
farm fields). Loss of top soil become a global problem for agriculture.
<span>A species that are occurring outside of its
normal distribution are known as Alien species. The cause of alien species is
that these species are not native to ecosystem and they can cause harm to the
environment.</span>
Answer: D) Pulmonary and aortic valves.
Explanation
There are two main heartbeats from a healthy heart.
The first beat is called the S1 or the lub, and it occurs when the atrioventricular valves (comprising the mitral and tricuspid valves) close.
The second beat is called the S2 or the dub, and it occurs when the semilunar valves (comprising the aortic and pulmonary valves) close.
Listening for heart beats is an essential part of cardiac auscultation.
Answer:
A. a lamp being turned on
B. a toaster being used to toast bread
D. a car horn honking
Explanation:
Energy transformation is the conversion of one form of energy to another form in accordance with the law of conservation of energy. According to this question, Phil is observing a flashlight, which turns chemical energy (batteries) into light energy.
From the examples given in this question, the following are examples of scenarios that involve energy transformation:
- A lamp being turned on: This converts chemical energy to light energy.
- A toaster being used to toast bread: This converts electrical energy to heat energy.
- A car horn honking: This converts electrical energy to sound energy.
Note that, melting of a chocolate does not transform any form of energy.
Density is a derived unit because it's not reported as a pure unit. (A pure unit would be something like kilograms or meters.) In contrast, the units for density are kg/m3. Density is the ratio of mass to volume; mass has the unit 'kilograms' (kg) and the unit for volume is cubic meters (m3).
Density is an intensive property, which means the amount of the material is irrelevant. The density of a substance is constant.