Заполни пропуски

Вычисли.

1. \(750+160=\) [ \(910\) | \(810\) | \(590\) ]
   \[ . 2. $340+280=$ [ $630$ | $610$ | $620$ ] \]
   .
2. \(800-460=\) [ \(430\) | \(440\) | \(340\) ].
3. \(320-160=\) [ \(160\) | \(180\) | \(260\) ].