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David leaves his house to go to school. he walks 200 meters west and 300 meters north. how far is david from his original starting point?

Recall that two angles are complementary if the sum of their measures is? 90°. find the measures of two complementary angles if one angle is twenty dash nine times the other angle.

The table below shows the approximate masses of a dust particle and a grain of pollen. dust particle 0.000000778 g grain of pollen 0.00000000155 g the mass of a dust particle can be estimated and written in the form a × 10^b, where a = 8 and b = the mass of a grain of pollen can be estimated and written in the form a × 10^b, where a = 2 and b = based on the estimates, the mass of a dust particle is approximately blank times larger than the mass of a grain of pollen.