The answer for:
20)
6x-7+6x³-4x-10x³-4-8x - 2x²= −43−22−6−11
19)
8u+6+7u+(-10) + (-5u) + 8= 10+4
The measure of ∠BEC would be 80 degrees
Answer:
Observational study
Step-by-step explanation:
There are 3 types of statistical study:
1) Experimental: Under this, any experiment is done on a certain group of population.
2) Observational: Under this study, the events are observed regularly and the record is made.
3) Survey : Under this study, a survey is conducted with a a group of population and the record is made.
According to question, A meteorologist keeps hourly temperature records over the course of several years in order to look for long-term variations, this is an example of <u>observational study</u>.
