It would be all the above
Descriptive investigations involve collecting data about a system, but not making tests or experiments.
Making tests belongs to experimental investigations.
Descriptive investigations aim to draw conclusions from observations of the fenomena, while experimental investigations design tests that let the researcher to compare results on different conditions with a control situation.
There is also the so called comparative investigations which collect data from under different conditions but do not include the control situtation.
The statement that is true about the population in <span>São Tomé and Príncipe is that it has the highest population but the lowest density in Central Africa. The correct answer is B. </span>
Answer:
Toothpastes generally contain the following components: Water (20–40%) Abrasives (50%) including aluminum hydroxide, calcium hydrogen phosphates, calcium carbonate, silica and hydroxyapatite. Fluoride (usually 1450 ppm) mainly in the form of sodium fluoride.
