I need help understanding how to do these problems, my teacher gave them as practice but didn't explain very well

1-For his exercise today, Felipe plans to both run and swim. Let r be the number of laps he runs and let s be the number of laps he swims. Each lap he runs takes him 4 minutes and each lap he swims takes him 2 minutes, he wants to exercise for more than 30 minutes today. Using the values and variables given, write an inequality describing this

2-To rent a certain meeting rom, a college charges a reservation fee of $18 and an additional fee of $6 per hour. The chemistry club wants to spend less than $60 on renting the room. What are the possible numbers of hours the chemistry club could rent the meeting room?