The four giant gas planets that are made primarily of lightweight elements are
a. earth, saturn, neptune, and venus.
b. venus, saturn, uranus, and neptune.
c. mercury, venus, earth, and neptune.
d. jupiter, saturn, uranus, and neptune.

The illuminance of a surface varies inversely with the square of its distance from the light source. if the illuminance of a surface is 120 lumens per square meter when its distance from a certain light source is 6 meters, by how many meters should the distance of the surface from the source be increased to reduce its illuminance to 30 lumens per square meter?

During the past 150 years in the united states, how did energy consumption compare to population growth

1. explain how you calculate the net force in any direction on the box. 2. suppose an upward force of 15n is added to the box. what will be the net vertical force on the box? 3. what force could be applied to the box to make the net force in the horizontal direction zero? explain. 4. suppose a force of 25n to the right is added to the box. what will be the net force to the right?