2.) Answer: Line
The intersection of two planes is a line. If the planes do not intersect, they are parallel. ... Furthermore, they cannot intersect over more than one line because planes are flat.
3.) Answer: Capacity
the maximum amount that something can contain.
Also-
(The capacity of a container is the volume of a container measured in liquid units. Cups, pints, quarts, and gallons are customary units of measurement. Two metric units of capacity are milliliters and liters. A milliliter is equal to about 20 drops from an eyedropper.)
-not really sure about no. 3-
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