Amanda says that a human fingernail has a thickness of about 4.2x10-4 meter. Justin says that a human fingernail has a thickness of about 0.42 millimeter A. What is the width in the meters written in standard notation?
B. Do Justin’s and Amanda’s measurements agree? Explain.
C. Explain why Justin’s estimate of the thickness of a human fingernail is more appropriate than Amanda’s estimate.

Which statement explains how you could use coordinate geometry to prove the opposite sides of a quadrilateral are congruent? a. use the slope formula to prove the slopes of the opposite sides are the same. b. use the slope formula to prove the slopes of the opposite sides are opposite reciprocals. c. use the distance formula to prove the lengths of the opposite sides are the same. d. use the distance formula to prove the midpoints of the opposite sides are the same.