Tlon Questions
3. Which is true about SPF ratings?
A. The highest rating is 100%
effective
B. The rating number means it will
protect you that many times
longer than without sunscreen
C. SPF ratings are only good in the
summer
D. SPF doesn't matter after 1 pm

B. The rating number means it will  protect you that many times  longer than without sunscreen

Explanation:

The sun protection factor is a comparison between the length of time it will take for a skin that has no sunscreen to begin reddening compared to a skin with sunscreen applied. Therefore, the ratings is an indication of the length of time a person will be protected from ultraviolet rays than when the individual has no sunscreen applied.

While higher SPF's are believed to offer more protection against UV rays, the added protection is usually just a negligible amount. They are very important for the skin and protect the body against diseases like cancer.

step 1 ammonium can be absorbed by plants, but some is converted into nitrates which are better for plants to absorb. this is called nitrification. 2. step 2 the deer eats the plants and uses the nitrogen-containing proteins for cell growth. 3. step 3 bacteria in the soil conduct nitrogen fixation to convert nitrogen gas from the atmosphere into ammonium. 4. step 4 some of the nitrates are absorbed back into plants, but denitrification breaks down the nitrates into nitrogen gas released back into the atmosphere. 5. step 5 nitrogen is found in the urine, which gets broken down into ammonium through the process of ammonification. 6. step 6 plants absorb the ammonium and begin assimilation, the process to add the nitrogen to protein.