Which of these is a correct step in constructing congruent line segments? Use a straightedge to draw two equal arcs from the endpoints.
Use a compass to join the endpoints of the line segment.
Use a straightedge to measure the length of the line segment.
Use a compass to create the distance between the endpoints.

The oldest rocks in the south atlantic ocean, immediately adjacent to the african and south american continental shelves, are 120,000,000 years old (time). calculate the average rate of seafloorspreading for the south atlantic ocean over its entire existence (hint: use formula: velocity = distance/time): /yr (velocity). now convert that to: cm/yr: