Need to understand topographical maps

Topographical maps deal with biological

1. 1999ft
2. East/ Northeast
3. Gradient equals slope. That equals 500 dividend by the distance btw c and d, the units are ft/mi

Ithink option a is correct because you cannot donate a different blood group than yours because it won't match.option a says betsy can donate to mark. they have the same blood group so donation can happen.

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