Answer:
Option D is the correct answer.
Step-by-step explanation:
the time out.
Time taken for back = t-1
We have plane's average speed out was 300 mph and average speed on the way back was 350 mph.
That is
Dividing both equations
Time taken for back = t-1 = 7-1 = 6 hours.
Read more on Brainly.com - brainly.com/question/1955818#readmore
Answer:
The radii of the circles are 12 cm and 7cm.
Step-by-step explanation:
Let the radii of the circles be 
Given:
Sum of circumference of two circles= 38π cm
Formula for circumference of a circle with radius r = 2πr
------------1
Sum of areas of two circles= 193π cm²
Area of circle with radius r = πr²
-------2
Substituting r2 = 19 - r1 in equation 2 we get:

Then r2 = 19 - r1

40 square units is teh correct answer