Final answer:
Mark runs 27 feet in 6 seconds.
Step-by-step explanation:
To find out how many feet Mark runs in 6 seconds, we need to determine how many yards he runs in 6 seconds first. We are given that Mark runs 6 yards every 4 seconds, so we can set up a proportion: 6 yards / 4 seconds = x yards / 6 seconds. Cross-multiplying and solving for x, we find that x = 9 yards. Now, since there are 3 feet in 1 yard, we can convert 9 yards to feet by multiplying by 3: 9 yards * 3 feet/yard = 27 feet. Therefore, Mark runs 27 feet in 6 seconds.