What exercise? Post a picture of it.
The correct answer is B. Secondary succession
Explanation:
In ecosystems, secondary succession occurs as certain events such as fires cause vegetation to temporarily disappear from one area. However, as soil is not affected negatively, vegetation grows again after some time, which means there is a secondary growth of vegetation and changes in the structure of an ecological community.
This term applies to the situation in the 1988 fires in Yellowstone Park because the fire destroyed the vegetation in the zone temporarily, but as the soil was intact after years or decades the vegetation will grow again, although this might implied changes in the ecosystem.

A dog meets all the characerisitcs of life in the following ways - they maintain homeostatis, are made of cells, breathe and have a metabolism, are able to reproduce, pass their traits off to their offsp they grow and change, and and respond to their environment.

Answer:
A: -65 degrees F; 70 degrees F
Explanation:
The Grand Canyon is made of sedimentary rock that contains fossils up to 1 billion years old. and the several upper layers of rock contain terrestrial, or land-based, fossils, such as dragonfly wing impressions and the footprints of scorpions, centipedes, and reptiles