Divide the distance by the speed:
(18 m) / (42 m/s) = 3/7 s ≈ 0.43 s
Well, first, let's recognize that there is no such thing as a force that is
balanced or unbalanced.
When we say that a group of two or more forces is balanced, we mean
that when you add up all the magnitudes and directions of the forces, the
whole group adds up to zero, so they have the same net effect as if there
were no force at all.

Actually Welcome to the concept of resistors,
The equivalent circuit is given as,
1/Rp = 1/3 + 1/6 + 1/9
1/Rp = 6+3+2/18
1/Rp = 11/18
Rp = 18/11 ==> 1.63 ==> 1.6 ohms
hence the equivalent resistance of the circuit is 1.6 ohms
The friends left on earth because they can see the total eclipse, where as you are on the moon witnessing sections get dark rather than the whole picture
Complete option to the question:
A. The asthenosphere is broken up into large continental- and ocean-sized plates.
B. Convection currents within the asthenosphere push magma upward to create new crust.
C. Heat from deep within Earth is thought to keep the asthenosphere malleable.
D. The asthenosphere is the repository for parts of the lithosphere that are dragged downward in subduction zones.
Answer: The correct option is A (The asthenosphere is broken up into large continental- and ocean-sized plates.)
Explanation:
Among the components that makes up the earth crust are the lithosphere and the asthenosphere.
The LITHOSPHERE is the outer layer of the earth structure which consists of the upper part of the mantle and the crust.
The ASTHENOSPHERE is a part of the upper mantle just below the lithosphere that is involved in plate tectonic movement and isostatic adjustments. It is denser and weaker layer of the upper mantle which permits the movement of tectonic plates in the lithosphere.
The asthenosphere is the repository for parts of the lithosphere that are dragged downward in subduction zones.Heat from deep within Earth is thought to keep the asthenosphere malleable. And the convection currents within the asthenosphere push magma upward to create new crust. But it is not broken up into large continental- and ocean-sized plates.