1)
2 + 6 : 3 * 2 - (-2)³ * 1/4 = 8,
1)) 6 : 3 * 2 = 4,
2)) (-2)³ * 1/4 = -8 * 1/4 = -2,
3)) 2 + 4 - (-2) = 2 + 4 + 2 = 8,
2)
9³ : 1/3 = 729 : 1/3 = 729 * 3 = 2187,
3)
(69² - 48²) / (21*83 + 34*21) = (69 - 48)(69 + 48) / (83 + 34)*21 =
= (21 * 117) / (117 * 2) = 1