Answer:

Explanation:
<u>Given:</u>
velocity of the ball first and ball second, 
angle of projection of the first ball, 
∵The balls should land at the same point,
∴their range of projectile,

As we know for the range of projectile:

∵ we have equal range in both the cases



![2\theta_2=sin^{-1}[sin 144^{\circ}]](https://tex.z-dn.net/?f=2%5Ctheta_2%3Dsin%5E%7B-1%7D%5Bsin%20144%5E%7B%5Ccirc%7D%5D)
![\theta_2=\frac{1}{2}\times sin^{-1}[sin 144^{\circ}]](https://tex.z-dn.net/?f=%5Ctheta_2%3D%5Cfrac%7B1%7D%7B2%7D%5Ctimes%20sin%5E%7B-1%7D%5Bsin%20144%5E%7B%5Ccirc%7D%5D)

A as an atom contains a nucleus where protons and neutrons are present. Electrons orbit the nucleus in paths called orbital
Answer:
1.92×10^-9 microCoulomb
Explanation:
Elemental charge = 1.6×10^-19 Coulomb
Charge of balloon after 12,000 electrons have been removed from it = 12,000 × 1.6×10^-19 Coulomb = 1.92×10^-15 Coulomb = 1.92×10^-15/10^-6 = 1.92×10^-9 microCoulomb