A theory predicts a reaction that produces ideal monatomic gas particles that have the following speeds: \(6.2 \mathrm{~m} / \mathrm{s}, 7. 4 \mathrm{~m} / \mathrm{s}, 7. 4 \mathrm{~m} / \mathrm{s}, 7. 8 \mathrm{~m} / \mathrm{s}, 8. 3 \mathrm{~m} / \mathrm{s}, 12. 6 \mathrm{~m} / \mathrm{s}\), \(20.1 \mathrm{~m} / \mathrm{s}, 20. 1 \mathrm{~m} / \mathrm{s}\). What are \((a)\) the average speed of the particles and \((b)\) their root-mean-square speed?