已知∠1+∠2+∠3=180°，∠1=30°，∠2=90°，求∠3．_爱下问搜题

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问题解答题

已知∠1+∠2+∠3=180°，∠1=30°，∠2=90°，求∠3．

答案

∠3=180°-∠1-∠2

=180°-30°-90°

=60°

答：∠3是60°．

选择题

Jim is always going to sleep with his bedroom light ______.[ ]

A．on

B．with

C．in

D．by

问答题简答题

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