试题分析：①首先计算乘法，然后计算加法；

②根据乘法分配律，计算即可；

③首先计算乘法，然后计算除法；

④首先计算除法，然后计算加法．

解：①7.2×0.8+1.04

=5.76+1.04

=7.8

②6.83×7.5+6.83×2.5

=6.83×（7.5+2.5）

=6.83×10

=68.3

③1.08×0.88÷0.27

=0.9504÷0.27

=3.52

④2.05÷0.82+33.6

=2.5+33.6

=36.1