<span>The high and low tide are caused by the gravitational forces between the earth and the moon</span>
Answer: sunlight.
Explanation: When trying to establish the level or extent of correlation or relationship which exists between two variables, the variables are classed as independent and dependent variables. The independent variable is referred to as the variable which causes a change in the value of the other variable (dependent variable). It is also known as the explanatory or predictor variable as it lead to changes in the dependent or predicted variable. In the scenario above, the independent variable is sunlight whose impact leads to changes in the growth level of the plant.
If producers were removed from an ecosystem, it would fall apart. Producers are the organisms at the bottom of the food chain, which produce glucose and nutrients for consumers. If producers were removed from an ecosystem, the consumers would have no nutrients and die, causing their predators to die, and so on.