Which of the following statements is true?

1) on a level surface, normal force equals weight.

2) the more inertia an object has, the more easily it will change its motion.

3) the more massive an object, the more quickly it will accelerate.

4) action-at-a-distance forces require physical contact between objects.

An important dimensionless parameter concerned with very high-speed flow is the mach number, defined as v/c, where v is the speed of the object such as an airplane or projectile, and c is the speed of sound in the fluid surrounding the object. for a projectile traveling at 1170 mph through air at 50 ˚f and standard atmospheric pressure, what is the value of the mach number?

Which type of energy would have nothing to do with ironing clothes? a. heat b. chemical c. electrical d. mechanical

Would it be correct to say the doppler effect is the apparent change in the speed of a wave due to the motion of the source? be sure to fully explain your position using at least 3 complete content related sentences.