Impulse = Force * time
Impulse = 500N *0.5 s =250 N*s
It has to due with numbers so I would say the last one!
Все написано в скобках правильно
Answer:

Explanation:
Speed of light is the product of its wavelength and frequency, expressed as
S=fw
Where s represent speed, f is frequency while w is wavelength
Making f the subject of the formula then
f=s/w
Substituting 2.99x10^8 m/s for s and 3.012x10^-12 m for w then

Therefore, the frequency equals to 
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