| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.38 |
| Score | 0% | 68% |
Water coming to a boil on a stove, ice melting, and steam from a cup of coffee are all examples of which of the following?
convection |
|
conduction |
|
radiation |
|
reflection |
Convection is the transfer of heat by the circulation or movement of the heated parts of a liquid or gas.
A human heart consists of how many chambers?
8 |
|
2 |
|
4 |
|
1 |
The heart is the organ that drives the circulatory system. In humans, it consists of four chambers with two that collect blood called atria and two that pump blood called ventricles. The heart's valves prevent blood pumped out of the ventricles from flowing back into the heart.
Which of the following is the formula for power?
\(P = {\vec{w} \over t}\) |
|
\(P = {w \over t}\) |
|
\(P = \vec{w}t\) |
|
\(P = w t\) |
Power is the rate at which work is performed or work per unit time: \(P = {w \over t}\) and is measured in watts (W).
Scavengers break down the dead bodies of plants and animals into which of the following?
complex carbohydrates |
|
producers |
|
carrion |
|
simple nutrients |
Like decomposers, scavengers also break down the dead bodies of plants and animals into simple nutrients. The difference is that scavengers operate on much larger refuse and dead animals (carrion). Decomposers then consume the much smaller particles left over by the scavengers.
Earth's history is divided into time periods, which of these is the longest time period?
age |
|
eon |
|
era |
|
epoch |
The Earth is approximately 4.6 billion years old and its history is divided into time periods based on the events that took place and the forms of life that were dominant during those periods. The largest graduation of time is the eon and each eon is subdivided into eras, eras into periods, periods into epochs, and epochs into ages.