When is it not necessary for a person to wear sunscreen during a recreational activity? a. when it's cold outside b. when it's not a sunny day c. when the activity is shaded by trees d. when the activity is indoors

The correct answer is D. when the activity is indoor

Explanation:

Sunscreen plays an important role in protecting the skin from sunburn and the ultraviolet rays coming from the sun. These ultraviolet rays can also harm you when it is not a sunny day or in winters or when you are playing under shaded trees.

Ultraviolet rays can not penetrate the building walls so when anyone is playing indoor then wear sunscreen during recreational activity is not necessary but any activity outside during day time requires sunscreen to protect the skin from harmful rays of sun. Therefore the correct answer is D.

to prevent people from getting the ebola virus, countries around the world paid to doctors develop a new vaccine. now that the vaccine has been made, doctors will need to experiment on a large number of people to find out if it works safely.

what is the greatest limitation that scientists are dealing with as they try to figure out how to experiment with the ebola vaccine?

meditation is a practice of sitting still and quiet for minutes or even hours. it has been practiced for thousands of years and is even a part of religious practices for some people. carefully controlled, repeated measurements of brain activity have shown that meditation does increase certain chemicals in the brain and even grows the part of the brain that people connect with their current surroundings and activities.

are claims about the effects of meditation most likely scientific or pseudoscientific?

not pseudoscientific, because people have made claims about it but scientific observations have not been made