Answer:
it cannot be easily degraded in our environment.Like humans, animals and plants are exposed to PBTs in the environment through air, water and food. ... Persistent bioaccumulative toxic substances (PBTs) are chemicals that do not degrade easily in the environment.
Answer:
Soil Erosion
Explanation:
Basically, tillage breaks soil up, destroying its overall structure. It encourages surface runoff and therefore soil erodes more easily. In some cases soil erosion is beneficial, but in most cases, it is not. Tillage has also been found to cause the emissions of more toxic gases such as N20.
Answer:
1 = A
2 = B
3 = B
Explanation:
1) Black holes occur when really big stars collapse on themselves. And, in order to get big, the star has to be an old one.
2) A black hole is something huge that swallows up everything, while a protostar is just the very beginning of a star.
3) Scientist can't truly know for sure, but they can infer about them due to the effects of the surrounding areas.
Answer:
Some don't because of many things, disease and not getting enough food.
Explanation:
