17da69153054840.png答案是（ ）。 A: 987 B: 1198 C: 774 D: 1014

1A=uA/ananas/latex/p/575

4.若有压圆管内水流为层流运动，则必有( )。 A: 9v/πdμ＜575 B: 9v/πdμ＜2300 C: 9v/πdv＜575 D: 9v/πdv＜2300

A metal surface illuminated by 8.5×1014 Hz light emits electrons whose maximum energy is 0.52 eV. The same surface illuminated by 12.0×1014 Hz light emits electrons whose maximum energy is 1.97 eV. The work function of the metal is (  B )

计算机信息存储单位1MB=（ ）KB。 A: 1000 B: 1014 C: 2014 D: 1024

氦—氖激光器发出波长为633nm的激光,当激光器的输出功率为1mW时,每秒发出的光子数为 A: 2.2×1015 B: 3.2×1015 C: 2.2×1014 D: 3.2×1014

自然数10的2进制码为（）。 A: 1010 B: 1012 C: 1011 D: 1014

以下哪些图像格式支持透明背景（） A: PNG/JPEG B: PNG/GIF C: JPEG/GIF D: BMP/PNG

Alana is not registered for sales tax purpose. She has recently received an invoice for goods for resale which cost $500 before sales tax, which is levied at 15%. The total value was therefore $575. What is the correct entry to be made in Alana's general ledger in respect of the invoice? A: Dr Purchases $500, Dr Sales tax $75, Cr Payables $575 B: Dr Purchases $575, Cr Sales tax $75, Cr Payables $500 C: Dr Purchases $500, Cr Payables $500 D: Dr Purchases $575, Cr Payables $575

常见的图像格式有（ ） A: MP4 GIF PNG PSD TIF B: JPG/JPEG GIF PNG PSD TIF C: JPG/JPEG RGB PNG PSD TIF D: CMYK GIF PNG PSD TIF