a) 2/3. 5/4-3/4.2/3 = 2/3. ( 5/4- 3/4)= 2/3. 1/2 = 1/3 b) 2.( -3/2)^2 - 7/2= 2. 9/4-7/2= 9/2 - 7/2 = 1 c) -3/4. 5 3/13-0,75. 36/13=-3/4. 5 3/13-3/4. 36/13 =-3/4.( 5 3/13+36/13 =-3/4. 8 =-6​
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