— What would you like in the future?
— I want to been engineer I grow up.
A:to do; before.
B:to doing; before
C:to doing; when
D:to do; when
图中的③是人体的肘关节部位.下列有关关节的叙述中,正确的是( )
如图所示,电源的内阻r=2.0Ω,电阻R=8.0Ω,开关闭合后,电流表示数I=0.30A,则电源的电动势E=____V; 在t=10s时间内,电阻R产生的热量Q=____J.