Please help me, really frustrated, question is due @ 11:59 tonight

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To solve the problem of finding the value of charge q that equates gravitational force to electrostatic force between the Earth and the moon, the gravitational attraction formula Gm_em_m/r^2 must equal the electrostatic attraction formula kq_1q_2/r^2. The discussion emphasizes that the gravitational force is based on the masses of the Earth and the moon, while the electrostatic force depends on their respective charges. Participants clarify that the user must equate these two forces to derive the correct value of q in coulombs. The thread reiterates that assistance will be provided, but the user is expected to engage with the problem rather than receive direct answers.
chrish
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hi, thanks for helping me.

heres the question

Suppose the moon had a net negative charge equal to -q and Earth had a net positive charge equal to +10q. What value of q would yield the same magnitude force that you now attribute to gravity?

(answer in coulombs) I have it on a thing called webassign, and you can only have 15 tries... i used 14. here are my wrong attempts:
1.6e-19
1.6e-18
-1.6e-18
-1.6e-20
1.6e-20
1.6e18
8.99e10
-8.99e10
.1
-.1
8.99e9
-8.99e9
-8.99e8
-10
 
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The gravitational attraction must equal the electrostatic attraction
\frac{Gm_em_m}{r^2} \ = \ \frac{kq_1q_2}{r^2}
 
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