The car is too expensive. He can't afford____ (pay) for it.
压力F/N
0
250
500
750
1000
1250
1500
1750
2000
…
电阻R/Ω
300
270
240
210
180
150
120
90
60
教师节到了,您给你喜爱的老师送了一朵玫瑰花,你送给老师的主要是( )
下列实验操作正确的是( )