What happens to the speed of molecules as temperature increases

What is tan(61)? а. 1.80 b. 0.49 c. 0.61 d. 0.87

You are traveling in a car going at a constant speed of 100km/h down a long, straight highway. you pass another car going in the same direction which is traveling at a constant speed of 80km/h. as measured from your car's reference frame this other car is traveling at −20km/h. what is the acceleration of your car as measured from the other car's reference frame? what is the acceleration of the other car as measured from your car's reference frame?

Ihave a density of 1.61g/cm^3 and a mass of 28g. find the missing value