But how many feet is he running each time?
Answer:
B. a ⊥ d
Step-by-step explanation:
If lines "a" and "d" are in the same plane, they are perpendicular to each other. If not, there is no relationship between the lines.
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Lines parallel to the same line are parallel to each other, so a║c. <em>In the same plane</em>, a line perpendicular to one of two parallel lines is also perpendicular to the other. (For example, one side of a rectangle is perpendicular to both of the adjacent sides, which are parallel to each other.)
The appropriate choice is ...
a ⊥ d
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<em>In 3 dimensions, ...</em>
Consider a cube. A given edge will be perpendicular to both of the two edges it meets at a corner.
It will not intersect (has no "perpendicular" relationship to) either of the edges parallel to those that meet at the corner at the other end of the space diagonal.
For 11a its 2:10 because how you would come up with it is by placing pablos free minutes first and then putting pablos paid minutes and 11b is8:25 because once again you would place sams free minutes first and then his paid minutes