**Newton's Second Law of Motion**

Newton's second law of motion states that the force \( F \) on an object is the product of its mass \( m \) with its acceleration \( a \).

\[ F = ma \]

If mass is measured in kilograms and acceleration in meters per second squared, then the force is given in newtons. Another way to measure force is in pounds; in fact, 1 newton is 0.225 pounds (which is about a quarter of a pound).

**Weight on the Moon**

Near the surface of the Earth, acceleration due to gravity is 9.8 meters per second squared. Acceleration due to gravity near the surface of the Moon is only 1.67 meters per second squared. Thus, an object has a different weight on the Earth than it would have on the Moon. What is the weight of a 95-kilogram man if he is standing on the Moon? Give your answer first in newtons and then in pounds. (Round your answers to two decimal places.)

**Gas Mileage Calculation**

For a truck that gets gas mileage of 19 miles per gallon, the number \( g \) of gallons required to travel \( m \) miles is given by:

\[ g = \frac{m}{19} \]

1. How many gallons are required to travel 31 miles?
(Round your answer to two decimal places.)

2. How many gallons are required to travel 210 miles?
(Round your answer to two decimal places.)

**Skydiver's Velocity**

When a skydiver jumps from an airplane, his downward velocity, in feet per second, before he opens his parachute is given by:

\[ v = 176(1 − 0.834t) \]

where \( t \) is the number of seconds that have elapsed since he jumped from the airplane. What is the velocity after 4 seconds? (Round your answer to two decimal places.) ft/s

**Carbon-14 Decay**

The amount \( C \), in grams, of carbon-14 remaining in a certain sample after \( t \) years is given by:

\[ C = 5 \times 0.5^{t/5730} \]

How much remains after 8000 years? (Round your answer to two decimal places.) g