The mass of an un identified rock is 15.5 grams. Students determine the volume of the rock by placing the rock in a cylinder with water. The students calculate the density of the rock. They determine the identity of the rock based on the density ranges table

True or false when elements combine to form a mixture, the resulting chemical properties may be very different from those of the elements that make it.

Samir watches a 100-minute movie on his spaceship. maria's spaceshipe flies in the same direction as samir's spaceship but she observes his move to last 125 minutes and his spaceship to be 40 m long. how long does samir observe his own spaceship to be? according to an observer on earth, planet x is stationary. maria and samir depart earth on their spaceships at the same time, each flying at 0.5c. maria flies toward planet x and samir flies in the opposite direction. according to maria, her voyage to planet x takes 9 years. how many years does marias voyage take according to samir?

Name two kinds of practical electric pumps.