Answer:
a wave with a time period of 2 seconds has a frequency of 1 ÷ 2 = 0.5 Hz. A sound wave has a time period of 0.0001 seconds.
 
        
             
        
        
        
Gravity is the force that pulls us to the surface of the Earth, keeps the planets in orbit around the Sun and causes the formation of planets, stars and galaxies.
        
             
        
        
        
Answer:
166 kg *m/s
44 N upward
39 m/s east
Explanation:
The short answer: If it has direction, it's a vector.
The long answer:
Vectors, unlike scalars, have direction. The first one, 166 kg*m/s is momentum, since momentum is velocity*mass, and velocity is a vector, momentum must be a vector.
44 Newtons is a vector since it has direction, in this case, upward. Force is acceleration*mass, and since acceleration is a vector, force must be a vector.
39 m/s is velocity, velocity has a direction, therefore it's a vector.
13.7 grams is mass since mass doesn't change with direction, it's a scalar, the opposite of a vector.
86 miles per hour has speed, but speed has no direction, therefore it's a scalar.
12 meters is distance, distance has no direction, therefore it's a scalar.
 
        
             
        
        
        
The student's average speed for the dash was 8.2 m/s. It's not possible to completely describe the student's velocity, because there's no information to tell us what direction she ran.