The frequency of a wave is just the reciprocal of the period.
For this one . . .
Frequency = 1/(period) = 1/(5 sec) = 0.2 per sec (0.2 Hz) .
The question is incomplete. The complete question is :
A platypus foraging for prey can detect an electric field as small as 0.002 N/C.
-To give an idea of sensitivity of the platypus's electric sense, how far from a +80nC point charge does the field have this magnitude?
Solution :
Given electric field, E = 0.002 N/C
Charge, Q = + 80 nC
or 
R = 600 m
This is the distance of the charge from the point of observations.
Answer:
a. Disk, 28 thousand light-years from
Explanation:
Since, a galactic disc is a component of disc galaxies, for instance spiral galaxies and lenticular galaxies. It consists of a stellar component and a gaseous component.
Also, the Sun lies within the galactic disk or in other words it is thought to be located in the galactic disk,
The Sun is located about 26,000 light-years away from the centre of the galaxy.
∵ From the given options 28,000 is nearest to 26,000
Hence, the sun is about 28 thousand light-years from the centre of the galaxy.
i.e. OPTION 'a' would be correct.
In what language are you speaking?
A: 132.9w because 2525\19 is how much energy transferred per second which is also known as the power
