[20 points]
earth's outer core can be modeled by a spherical shell that extends from a distance of approximately 1,200 kilometers from earth's center to approximately 3,400 kilometers from earth's center. which of the following is closest to the volume of earth's outer core, in cubic kilometers?
a) 1.52 x 10^7
b) 3.18 x 10^7
c) 4.46 x 10^10
d) 1.57 x 10^11
!

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 0 a. at what time does the particle reverse direction? b. when is the displacement positive? (round one decimal place and answer in interval notation) c. when is the displacement negative? (round one decimal place and answer in interval notation) d. when is the particle’s acceleration positive? (round one decimal place and answer in interval notation) e. when is the particle’s acceleration negative? (round one decimal place and answer in interval notation)

Given the sequence 7, 14, 28, 56, which expression shown would give the tenth term? a. 7^10 b. 7·2^10 c. 7·2^9

What is 617.3 miles and each gallon of gas the car can travel 41 miles select a reasonable estimate of the number of gallons of gas karl used.