Answer:
324π in²
Step-by-step explanation:
The surface area of a sphere = 4πr² ( r is the radius )
Calculate r using the volume (V) formula
V = πr³
Here V = 972π , thus
πr³ = 972π ( divide both sides by π )
r³ = 972 ( multiply both sides by 3 to clear the fraction )
4r³ = 2916 ( divide both sides by 4 )
r³ = 729 ( take the cube root of both sides )
r = = 9
Thus
surface area = 4π × 9² = 4π × 81 = 324π in²
Answer:
<em>Her speed driving in nice weather is 50 mph and in thunderstorm is 32 mph.</em>
Step-by-step explanation:
Barbara drives 50 miles in clear weather and then encounters a thunderstorm for the last 16 miles.
Suppose, her speed in nice weather is mph.
As she drives 18 mph slower through the thunderstorm than she does in clear weather, so her speed in thunderstorm will be:
<u>We know that,</u>
So, <u>the time of driving in clear weather</u> hours
and <u>the time of driving in thunderstorm</u> hours.
Given that, <u>the total time for the trip is 1.5 hours</u>. So, the equation will be......
Using zero-product property.........
<em>We need to ignore here, otherwise the speed in thunderstorm will become negative.</em>
So, her speed driving in nice weather is 50 mph and her speed driving in thunderstorm is (50-18) = 32 mph