The correct frequency of exercise in order for it to be effective

Explain what causes the skin to burn in the sun? explain why people should avoid the sun if taking a photosensitive medication?

If you know answer will mark brainliest

What is the difference between a license and a certificate in the healthcare system? a. a certificate grants the freedom to practice, while a license only confirms professional qualifications. b. a license grants the freedom to practice, while a certificate only confirms professional qualifications. c. medical doctors receive licenses, and nurses receive certificates. d. medical doctors receive certificates, and nurses receive licenses. i'll give you 30