# Help with easy problems that I just can't seem to get right

I think I am doing these right, but I keep getting them wrong...can anyone show me what I am doing wrong.

1. What is the wavelength of a 29.00E9 Hz radar signal.
I did wavelength = c/f = 3.00E8m/s divided by 29.00 Hz and got 0.01034, but it is telling me that it is wrong.

2. An em wave has a wavelength of 850nm, what is the frequency.
I did f = c/wavelength = 3.00E8m/s divided by 850E-9 m and got 3.53E14, and it told me it was wrong.

3. Calculate the frequency of green light with a wavelength of 540nm and yellow light with a wavelength of 580nm. I did freq of green = c/wavelength = 3.00E8/540E-9 and got 5.56E14 which was wrong, and 3.00E8/580E-9 = 5.17E14 which was also wrong.

4. A start is 2.1 light years away. How far is it away in meters? I converted 2.1 years to seconds, and then divided 3.00E8/2.1 years in seconds and got 9.06m, which was also wrong.
I know these problems are easy but I am frustrated with them because I can't get them right, I would really appreciated it if someone could help me out.

supermenscher said:
... but it is telling me that it is wrong.
What is "it"? Are you submitting these answers online or something? Or does "it" refers to the answers in your book? Do you have these answers? Can you post these answers?

It is submitting the answers online