1. What causes the change in your role in the various speaking situations you have at home, in the school and the community?​

What causes these changes are interpersonal interactions, the degree of intimacy and the degree of formality.

Explanation:

Our speaking situations are modified, basically, by the relationship established between us and the listener, as well as our degree of intimacy and formality of the place where we are. In this case, we can affirm that in our family and in our community, we establish relationships of less formality and more intimacy, which allows a less formal and more relaxed communication. At escalo, we can also present this type of interaction, as we can present a more formal interaction that requires more cultured and rigid communication.

Radioactive tracers are widely used to diagnose industrial reactors, for instance by measuring the flow rate of liquids, gases and solids.

Explanation:

Radioactive tracers are widely used to diagnose industrial reactors, for instance by measuring the flow rate of liquids, gases and solids. A radioactive tracer is a chemical compound in which one or more atoms have been replaced by a radioisotope.

heres the link for more information

https://www.iaea.org/topics/radiotracers#:~:text=Radioactive%20tracers%20are%20widely%20used,been%20replaced%20by%20a%20radioisotope

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