Two friends Al and Jo have a combined mass of 168 kg At an i

Two friends, Al and Jo, have a combined mass of 168 kg. At an iceskating rink they stand close together on skates, at rest andfacing each other, with a compressed spring between them. Thespring is kept from pushing them apart because they are holdingeach other. When they release their arms, Al moves off in onedirection at a speed of 0.84 m/s, while Jomoves off in the opposite direction at a speed of 1.2 m/s. Assuming that friction is negligible, findAl\'s mass.
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