0.279
2.48
5.75
58.6
(1)6.5×6.5+6.5×3.5
=6.5×(6.5+3.5)
=6.5×10
=65
(2)2.5×（2.4+0.8）×1.25
=2.5×3.2×1.25
=(2.5×4)×(0.8×1.25)
=10×1
=10
(1)1.8+(1.8×2-0.6)
=1.8+(3.6-0.6)
=1.8×3
=5.4
(2)3.75÷0.25-1.8×4.5
=15-8.1
=6.9
(3)(4.4×2.5+19)÷3
=(11+19)÷3
=30÷3
=10