Two planes start from the same airports and fly in opposite directions. the second plane starts 1/2 hour after the first plane, but it's speed is 70 kilometers per hour faster. find the ground speed of the first plane if 1 hour after the first plane departs the planes are 3980 kilometers apart.

The box plots show the distributions of the numbers of words per line in an essay printed in two different fonts.which measure of center would be best to compare the data sets? the median is the best measure because both distributions are left-skewed.the mean is the best measure because both distributions are left-skewed.the median is the best measure because both distributions are symmetric.the mean is the best measure because both distributions are symmetric