The following are the durations in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier. Time (in minutes) Relative Frequency 0 but less than 5 0.37 5 but less than 10 0.22 10 but less than 15 0.15 15 but less than 20 0.10 20 but less than 25 0.07 25 but less than 30 0.07 30 or more 0.02 If 1,000 calls were randomly sampled, how many calls laasted under 10 minutes?
A、220
B、370
C、410
D、590