Answer: wavelength is 
The frequency of the microwave is, f = 2.30 GHz.
To Find frequency use the formula:
λ
Where, c is the speed of electromagnetic wave or light. f is the frequency, and λ is the wavelength of light.
Rearranging, 
Plug in the values,
Answer:
It takes 77 N
Explanation:
Using Newton's second law of motion, F=ma (Force equals mass times acceleration. Since the mass of the couch is 385 kg and the target acceleration is 0.2 m/s, you simply multiply mass times acceleration (ma) to get the total force, or 77 N.
The force pushing down is the force of Gravity. On a chair it is in perfect balance with the force pushing up (the normal force)
in terms of magnitude
FN = FG = mg
the forces are in opposite direction
hope this helps
Ionic compounds are made up of two charged species, a cation (+) and an anion (–).
The charges must balance out to zero for a stable ionic compound, because ionic bonds are formed between two charged species. They form in ratios according to their charges to balance out.
