The clock will read 4:50 by the time Tomas leaves the class.
The clock makes a complete cycle every 4 seconds. This means that 4 seconds make a minute as far as the clock is concerned.
Tomas entered the class at 9:00 am and left at 9:50 am. This means he used a total of 50 minutes.
50 x 60 = 3,000 seconds
Recall that: 4 seconds = 1 minute for the clock
3,000/4 = 750 minutes
750/60 = 12.5 hours
Add 12.5 hours to 4:20 = 4:50
More on time calculation can be found here: https://brainly.com/question/20416068
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