What is the difference between an element and a compound in terms of these models? ( asap)

Acar travels in reverse. it covers 150 meters in 12 seconds what is the velocity of the car what is the speed of the car

Which of the following is a true statement about the acceleration ~a of the pendulum bob ~a is equal to the acceleration due to gravity. ~a is perpendicular to the bob’s trajectory. ~a is equal to the instantaneous rate of change in velocity. ~a is tangent to the bob’s trajectory.

How many moles if mgcl2 are there in 340g of the compound?