In the diagram below chords AB and CD intersects at E. If mAC=72 and mAEC=58. how many degrees are in mDB?

44°

Step-by-step explanation:

∠ DEB and ∠ AEC are vertical and congruent

Thus ∠ DEB = 58°

The measure of the chord- chord angle DEB is half the sum of the measures of the arcs intersected by the angle and its vertical angle, that is

(DB + AC ) = 58° ( multiply both sides by 2 )

DB + AC = 116°, that is

DB + 72° = 116° ( subtract 72° from both sides )

DB = 44°

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m

answer: 819.89 miles across america

step-by-step explanation: