To solve this problem we will apply the concepts related to the potential, defined from the Coulomb laws for which it is defined as the product between the Coulomb constant and the load, over the distance that separates the two objects. Mathematically this is

k = Coulomb's constant
q = Charge
r = Distance between them


Replacing,



Therefore the potential at the surface of the raindrop is 135 V
Answer:
1.t=-1.96sec
2.H=4.8m
3.T=1.96sec
4.R=19.2m
Explanation:
u=9.8,t=?,sin theta=1
using formula t=2usintheta/g
t=2x9.8x1=19.6/10
t=1.96seconds
using formula H=u(squared)sin(squared)theta/2g
H=9.8(squared)x1(squared)/2x10
H=96x1/20
H=96/20
H=4.8m
using formula T=2usintheta/g
T=2x9.8x1/10
T=19.6/10
T=1.96sec
using the formula R=u(squared)sin2theta/g
R=9.8(squared)x2/10
R=96x2/10
R=192.08/10
R=19.2
B. How many people were included in the study.