what are radioactive substances what is fusion does it happen in the sun hw old - Science - Physical and Chemical Changes

Question

what are radioactive substances ? what is fusion ? does it happen
in the sun? hw old is the sun? how was it made or how did it become
?

Ravjot Kaur · Accepted Answer

Dear student
Please refer to the following links:

https://www meritnation
com/ask-answer/question/what-is-radioactive-substance/nuclei/605108

https://www meritnation
com/ask-answer/question/define-nuclear-fusion/sources-of-energy/327109

Kindly post remaining queries in separate threads
Regards

what are radioactive substances ? what is fusion ? does it happen in the sun? hw old is the sun? how was it made or how did it become ?