Also visible light with a wavelength of 480nm appears

a violet
b green
c blue
d red

microwave have a wavelength and frequency than radio wave

a longer, higher
b longer, lower
c shorter, higher
d shorter, lower

need

a) The correct answer is

C blue

In fact, we see from the electromagnetic spectrum in the figure that light with wavelength of 480 nm corresponds to blue light.

b) The correct answer is

C shorter, higher

In fact, microwaves have wavelengths between 0.1 cm and 1.0 m, while radio waves can have wavelength of several metres, so microwaves have shorter wavelength than radio waves. Since the frequency of a wave is inversely proportional to its wavelength, this also means that microwaves have higher frequency than radio waves.

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.