Jill has a gel pen. The gel pen has a mass of 8g and a volume of 2cm3. What is the density of the rock?

Achlorine atom has 17 protons and 18 neutrons. what is its mass number? what is its atomic number?

Place me with this question is my last question

Amachinist turns the power on to a grinding wheel, at rest, at time t = 0 s. the wheel accelerates uniformly for 10 s and reaches the operating angular velocity of 96 rad/s. the wheel is run at that angular velocity for 40 s and then power is shut off. the wheel slows down uniformly at 1.5 rad/s2 until the wheel stops. in this situation, the time interval of deceleration is closest to: