— Maggie, what you said may result in serious problems.
— I see. I was just telling the truth.
A:cause
B:solve
C:become
(Ⅰ)求l的普通方程和C的直角坐标方程;
(Ⅱ)当φ∈(0,π)时,l与C相交于P,Q两点,求|PQ|的最小值.
如图,用一定频率的单色光照射光电管时,电流表指针会发生偏转,则( )