Ecosystems equilibrium is when populations of organisms in the ecosystem are balanced.
The correct answer is (a) driving.
The pressence of undesirable substances in air is called as air pollution. There are many human activities that contribute to air pollution. The biggest contributor is driving. The pollutants that comes out of the car are carbon dioxide, carbon monoxide. They also release hydrocarbon and nitrogen oxides which when combines in sunlight becomes ozone. Air pollutants emitted by cars and other automobiles increases the level of harmful gases which to severe health problems such as heart disease, asthma, irritation in eyes.
it's a summary of the number of individuals of each age in the population. Age structure is useful in understanding and predicting population growth. An understanding of population age structure is critically important to industries that harvest living organisms.
hope that i helped :)