Why is it important to have only one independent variable in a scientific experiment?

What is the main reason why some developing countries fear the increase the free trade policies around the world?

Air can be considered a mixture. which statement does not explain why?

Read the claim. breakfast is an important meal. it jump starts the body’s process of using calories to break down food. appetite can decrease with age, but going too long without eating causes metabolism to slow down. current research shows that incorporating legumes such as lentils and chickpeas into meals boosts metabolism for twenty-four hours. who might benefit from this claim? people who have a fast metabolism stores that sell exercise equipment people who take vitamin supplements grocery stores that sell legumes