Which part of the human body regulates temperature through sweating and blood vessel dilation?

Which everyday device converts direct current into alternating current for household appliance use?

Which type of animal can live both on land and in water, such as frogs and toads?

Which enzyme present in saliva begins the digestion of starch in the mouth?

Which blood type is known as the universal donor for blood transfusions?

Which scientific law explains that every object attracts every other object with a force proportional to their masses?