对于愈演愈烈的送礼风、人情风,教师对家长采取各种方式表达“心意”,最好的办法是(),不给学生、家长的各种表达“心意”机会
If the dispersion of a given fiber is 17ps/nm*km at 1550 nm and zero at 1310 nm, then what is the accumulated dispersion of an ITU wavelength after it travels 200 km? () [" 0 ps\/nm"," 340 ps\/nm"," 200 ps\/nm"," 3400 ps\/nm"," More information is needed."]
我国古代自秦汉以来中央和地方管制演变的基本趋势是()。①消弱地方,加强中央②消弱相权,加强君权③对边疆地区的管辖和治理日趋严密④逐渐强化对地方官吏的控制和监视 ["①②③④","①②③","②③④","①②③"]
What are three relevant design considerations when using the 15216 EDFA? ()(Choose three.) [" dispersion"," Optical SNR"," span attenuation"," four wave mixing"," receiver sensitivity"]
点火线圈主要由()和()等组成。
请简述程序设计的一般步骤。