Final answer:
Gray whales developed physical adaptations such as increased height, a single large toe that turned into a hoof, and longer, cement-covered molars to help them persistently forage for food.
Step-by-step explanation:
The gray whales experienced physical adaptations when they persistently foraged. They became taller to see predators while feeding in tall grasses, evolved a single large toe that eventually became a hoof to run swiftly, and their molars became longer and covered with cement to grind tough grasses and grass seeds without wearing out their teeth. These adaptations allowed them to survive and thrive in their habitat.