To solve this problem it is necessary to apply the concepts related to the principle of superposition and constructive interference, that is to say everything that refers to an overlap of two or more equal frequency waves, which when interfering create a new pattern of waves of greater intensity (amplitude) whose cusp is the antinode.
Mathematically its definition can be given as:

Where
d = Width of the slit
Angle between the beam and the source
m = Order (any integer) which represent the number of repetition of the spectrum, at this case 1 (maximum respect the wavelength)
Since the point of the theta angle for which the diffraction becomes maximum will be when it is worth one then we have to:


Applying the given relation of frequency, speed and wavelength then we will have that the frequency would be:

Here the velocity is equal to the speed of light and the wavelength to the value previously found.


Therefore the smallest microwave frequency for which only the central maximum occurs is 1.5Ghz
Answer:
upthrust or BUOYANT FORCE =Vdg
volume=LWH
upthrust=(4cm×5cm×2cm)×1g/cm²×g
upthrust=40cm³×1g/cm³×g
upthrust=40gf or 0.04kg×10m/s²=0.4N
weight of the displaced liquid is upthrust.
so mass=40g or 0.04kg
upthrust=40gf or 0.4Nand mass of the displaced liquid=40g or 0.04kg
please mark brainliest, hope it helped
Helps living things survive cuz they need water just like humans