Answer:

Explanation:
1. Distance from epicentre
The average speed of P-waves is about 8 km/s.
(a) Convert minutes to seconds

(b) Calculate the distance

2. Time for S-wave
The average speed for an S-wave is about 3.45 km/s.

Answer:
The answer is A I believe
Explanation:
Answer:
They are stimulated by an antigen.
Explanation:
Natural killer cells are cytotoxic cells that help our body in innate immune response. These are an critical and important component of the innate immune system of our body. These natural killer cells provide a rapid response towards the virus infected cells. These cells have capability to detect MHC that are present on the infected cells. Natural killer cells do not require activation for killing those cells which are missing MHC I. Due to this feature, they are named as the Natural killer cells. These cells can directly induce the death of tumor cells and play an important role in immunosurveillance.
On a Journey to and island i would take a Blade. The blade will he useful to cut tress to make various sorts of Things such as bark to start fires and Bamboo to make beds/tools. Also the blade will help me hunt Food and cut the meat to make it edible.
On the journey i would also take Fire starters because you need a fire for various of things. With the fire you made from the fire starters you can cook food and clean water for survival. Also you can Keep warm during the cold with said fire.
From molecule, cells, tissue,organ, organ system,organism
And from organism to the population, community, ecosystem, and biosphere :)