To make a living,they are willing to ________ many of the disadvantages of city life such as crime,heavy traffic and pollution. ( )
A:put up
B:put off
C:put up with
D:put away
下列有关叙述正确的是( )
理想变压器原、副线圈匝数之比为2:1,原线圈接入如图乙所示的正弦式交流电压,副线圈接一个R=55Ω的负载电阻,电流表、电压表均为理想电表,则下述结论正确的是( )
现在提供鼠妇20只、硬纸盒、湿泥土、记录本、计时器、手电筒、纸板和玻璃板等供你选用,请设计一个探究光照是否影响鼠妇生活的实验。
(1)图1中被测物体的长度为 ____ cm
(2)图2中弹簧测力计的读数为 ____ N.