` 1,`
`b) 75 - (3.5^2 - 4.2^3 )`
`= 75 - ( 75 - 32 )`
`= 75 - 75 + 32`
`= 32`
`2,`
`b) 189 + 73 + 211 , 127`
`= ( 189 + 211 ) + ( 73 + 127 )`
`= 300 + 200`
`= 500`
` 3,`
`b) 5 . 3^2 - 32 : 4^2`
`= 45 - 2 . 4^2 : 4^2`
`= 45 - 2`
`= 43`
`4,`
`b) 80 - ( 4 . 5^2 - 3 . 2^3 )`
`= 80 - ( 4 . 25 - 6 . 4 )`
`= 80 - 4(25 - 6)`
`= 80 - 4 . 19`
`= 80 - 76`
`= 4`
`5, `
`b) 128.19 + 128.41 + 128.40`
`= 128( 19 + 41 + 40)`
`= 128 . 100`
`= 12800`
`6, `
`b) 375 + 693 + 625 + 307`
`= ( 375 + 625 ) + ( 693 + 307 )`
`= 1000 + 1000`
`=2000`