If a car is travelling 70 m.p.h that means it is travelling 70 miles PER HOUR and since we want to know half an hour we can do
70mph divided by 2 =35m.p half hour so the car is travelling 35miles in half an hour
Answer- Helium
You can by the number of protons, and if you look at a periodic table the atomic number of helium is the same as the number of protons
As proton is heavier then electron, and electrostatic force is directly proportional to mass, so it would be greater and direction would be changed 'cause of different charges.
In short, Your Answer would be Option 4
Hope this helps!
Answer:
The pressure is 6570 lbf/ft²
The temperature is 766 ⁰R
The velocity is 2746.7 ft/s
deflection angle behind the wave is 17.56⁰
Explanation:
Speed of air at initial condition:

γ is the ratio of specific heat, R is the universal gas constant, and T is the initial temperature.
initial mach number

then, 
based on the values obtained, read off the following from table;
P₂/P₁ = 3.285
T₂/T₁ = 1.473
Mₙ₂ = 0.6355
Thus;
P₂ = 3.285P₁ = 3.285(2000) = 6570 lbf/ft²
T₂ = 1.473T₁ = 1.473(520⁰R) = 766 ⁰R
Again; to determine the velocity and deflection angle, first we calculate the mach number.





Answer:
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