all of the above cause the cardiovacular system help you move your blood
We will use the Descartes` rule of signs and see how many times the signs change from positive to negative and from negative to positive from one term to the next ( two consecutive terms are with different signs ).
In this case it is 4 times ( +7x13 to -12x9, -12x9 to +16x5, +6x5 to -23 x and finally -23x to +42 ).
Answer: There are 4 real zeroes.
Plants, microorganisms, and animals
It would be Primary because the lake is it’s starting point and the pollution grew all the way to the factory.
