An object weighs 3 lb. at 10 earth radii from its center. What is the object's weight on the earth's surface? lb. 3
30
300
3,000

The weight is the same  

3 lb

explanation

See explanation.

Explanation:

If by weight you mean the physical value measured in  

l b  (or  k g ) usually called mass, then this value does not depend on a place where object is located. Object's mass would be the same everywhere even if you put it on Mars or the Sun.

The value which changes is the gravitational force. In your example it is  

10 2 = 100  times greater on the Earth's surface than in the point  10  Earth's radii from its center.

305.7

explanation:

density =m/v

density =917/3.00

density = 305.

approximately = 305.7

in four significant figures

energy stored in the capacitor= 9.72 x 10⁻⁴ j

explanation:

the energy stored in the capacitor is given by

e= 1/2 c v²

e= energy stored

c= capacitance= 1.5 µc= 1.5 x 10⁻⁶f

v= potential difference=36 v

so energy stored= e= 1/2 (1.5 x 10⁻⁶) (36)²

energy stored= 9.72 x 10⁻⁴j