I think it's A even though I think it's 400 to 700 but maybe I'm just thinking backwards but anyways it's probably A
Hope I helped in some way
Answer:
All the statements are true and the correct option is;
D. All of these are true
Explanation:
Ecosystems change over time. ... Sudden disruptions such as volcanoes, floods, or fires can affect which species will thrive in an environment. Other disruptions are caused by human activities
An ecosystem ecosystem is an area where a community living (biotic) and non living (abiotic) things such as plants, animals, other organisms, landscape, natural sources and weather interact to create an apparently sustainable system
An ecosystem undergoes several changes over time due to environmental disturbance which results in the variation of the ecosystem's structure and change rate due to the natural disturbance and/or human activity
Therefore all the statements are true.
For much of the last quarter century, the leading theory of the driving force behind tectonic plate motions envisaged large scale convection currents in the upper mantle, which can be transmitted through the asthenosphere.
Receptors in muscles provide the brain with information about body position and movement. The brain controls the contraction of skeletal muscle. The nervous system regulates the speed at which food moves through the digestive tract.Your muscular system is closely connected to the nervous system. That makes sense since you usually have to think before you can move. Even though thinking is not always involved, the neurons of the nervous system are connected to most of the cells in your muscular system.
