7. Three students traveled from Charlotte, NC to Anderson, SC. Ollie traveled by bus at 68mph south. Aggie traveled by train at 45 km/hour. Pete
flew at 310 mph. Which of the students represents a velocity? *
A. Ollie; He was on the ground and traveled in the units of mph.
B. Aggie; She traveled in units that were metric.
C. Pete: He flew and got there the fastest.
D. Ollie; It includes a direction.

Explain to someone who knows nothing about fossils the study of invertebrate paleontology and how it scientists understand the history of the earth. be sure your explanation contains a minimum of two complete sentences.

The uniform slender bar rests on a smooth horizon- tal surface when a force f is applied normal to the bar at point a. point a is observed to have an initial acceleration aa of 20 m/s2, and the bar has a corre- sponding angular acceleration of 18 rad /s2. deter- mine the distance b.

As you are trying to move a heavy box of mass m, you realize that it is too heavy for you to lift by yourself. there is no one around to , so you attach an ideal pulley to the box and a massless rope to the ceiling, which you wrap around the pulley. you pull up on the rope to lift the box. use g for the magnitude of the acceleration due to gravity and neglect friction forces. once you have pulled hard enough to start the box moving upward, what is the magnitude f of the upward force you must apply to the rope to start raising the box with constant velocity? express the magnitude of the force in terms of m, the mass of the box.