The answer is:
B)They are in the same group because they have similar chemical properties, but they are in different periods because they have very different atomic numbers.
The explanation:
The vertical columns on the periodic table are called groups or families because of their similar chemical behavior. All the members of a family of elements have the same number of valence electrons and similar chemical properties.
A period is a horizontal row of elements on the periodic table. For example, the elements sodium ( Na ) and magnesium ( Mg ) are both in period 3. The elements astatine ( At ) and radon ( Rn ) are both in period 6.
There are many principles that are classified under the Gestalt Principles. The Gestalt principles believe that any stimulus can be viewed in a very simple form. According to the given image, I can say that the square represents the Gestalt principle of PROXIMITY. Hope this helps.
force of friction on the cart is given as

here we also know the reaction force due to surface

so we can say reaction force is given as




now by force balance we will say



also we know that



now minimum force required to set this into motion

here we know that



So it will require 259 N minimum force to move it
Answer:
60 rad/s
Explanation:
∑τ = Iα
Fr = Iα
For a solid disc, I = ½ mr².
Fr = ½ mr² α
α = 2F / (mr)
α = 2 (20 N) / (0.25 kg × 0.30 m)
α = 533.33 rad/s²
The arc length is 1 m, so the angle is:
s = rθ
1 m = 0.30 m θ
θ = 3.33 rad
Use constant acceleration equation to find ω.
ω² = ω₀² + 2αΔθ
ω² = (0 rad/s)² + 2 (533.33 rad/s²) (3.33 rad)
ω = 59.6 rad/s
Rounding to one significant figure, the angular velocity is 60 rad/s.
Of the list, Ultraviolet waves have the shortest wavelength