Answer:
D)Gases usually weigh less than solids.
Answer:
the answer is B Astroid Belt
Answer:
Observational study
Explanation:
An investigation of what happened over the years to the people who were exposed to radiation during the 1986 Chernobyl nuclear disaster would be termed <u>an observational study</u> because it will require observing subjects and finding out if there is a kind of correlating factor in the subjects that could indicate the level of exposure to the nuclear radiation.
There are basically two types of research studies:
1. Observational studies
2. Experimental studies
Observational studies involve just the observation of subjects and trying to find out some correlation factors. This kind of study could be prospective when it deals with what could happen in the future based on certain factors or retrospective when it considers what has already happened. An observational study can be cross-sectional, case-only, case-control, or cohort study.
Experimental studies are also referred to as randomized or controlled trial studies. Here, subjects are grouped and each group receives a different treatment in order to isolate the effect of a particular factor or variable relating to the treatment.
Answer:Predatorrrrrrrrrrrrrrrr
Pls gimme Brainliest
<h3>
Answer:</h3>
<h3>
Explanation:</h3>
As we know in oxidation, oxygen is added and hydrogen is reduced. And in option B, we can observe that is oxygen added +6. So, we conclude that option B is valid.
<h3>Hope it help you</h3>
