Given a scientific passage and an answer, generate a question for the given answer.

Passage: The power of the ocean modifies landforms by erosion and deposition. Landforms modified by both erosion and deposition are seen in this photo. The cliff is being eroded by incoming waves. The beach is being created as sand is being deposited. Answer: erosion and deposition
By what processes does the ocean modify landforms?

Passage: Condensation reactions are the chemical processes by which large organic compounds are synthesized from their monomeric units. Hydrolysis reactions are the reverse process. During condensation reactions, water is produced from the two molecules being bonded together; an H from one monomer is joined to an -OH from another molecule, producing H 2 O. Answer: water
What is produced during a condensation reaction?

Passage: p = F nett, we can see how the change in momentum equals the average net external force multiplied by the time this force acts. The quantity F net t is given the name impulse. Impulse is the same as the change in momentum. Impulse: Change in Momentum Change in momentum equals the average net external force multiplied by the time this force acts. Answer: momentum
Change in what equals the average net external force multiplied by the time this force acts?