Understanding perpendicular and parallel lines are extremely important, especially in the engineering field when building infrastructures or houses because they need to calculate how they will keep a building stable. For example, bridges we see have a lot of perpendicular and parallel lines, that's because without those the bridge can't hold itself up, it needs support from the metals that are parallel and perpendicular.
hope this helps!!
15 Minutes
You have 8 km in an hour.
Divide all that by two and you'll have 4 km in 30 mins.
Then divide by two again to end up with 2 km in 15 mins.
You could alternatively divide by four from the beginning, but I find this easier.
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