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Problem 5. Rest periods can be calculated according to the following empirical formula [Murrell, 1971]: w(b -s) Rest allowance = b -0.3 Where w is the length of the working period, b is the oxygen uptake, s is the standard uptake for continuous work A worker spends 15 min loading boxes onto a truck. His oxygen uptake is 2 L/min. If the standard is taken to be 1 L/min, what rest allowance would he be given