Answer:
Stop exercising and sit in a cool place.
Step-by-step explanation:
Heat cramps happen when a person is active during hot weather, like Klaus, who is playing basketball at noon during the summer. As this is a symptom of heat-related illness, what he should do is stop exercising, stretch his abdomen, go to a cooler place such as under the shade of a tree or inside, and drink water. The body has lost its balance due to the extreme heat and intense activity. To help it, we have to do the mentioned steps. Otherwise, the symptoms will worsen, and he could suffer from a heat stroke.