How many times stronger is the hydrogen-ion concentration of a pH 4 solution as compared with a pH 9 solution?

Both digestion and absorption happen in the small intestine. Digestion is the process by which food is broken down into small molecules that the body can absorb and use for energy, growth, and repair. The final products of digestion are absorbed from the digestive tract, primarily in the small intestine.

The other options are not correct because they do not accurately describe where both digestion and absorption happen in the digestive system. The gallbladder stores bile produced by the liver, but does not play a direct role in digestion or absorption. The esophagus transports food from the mouth to the stomach, but does not play a direct role in digestion or absorption. The stomach plays a role in digestion by churning food and mixing it with gastric juices, but most absorption occurs in the small intestine.

The doctor refuses to prescribe antibiotics to the patient because the illness is caused by a virus. The common cold is a viral infection of the upper respiratory tract ⁴. Antibiotics are not effective against viral infections and are only used to treat bacterial infections.

The other options are not correct because they do not accurately describe the cause of the common cold and sore throat. Fungus, protist, and bacteria are not the pathogens responsible for causing the common cold .