"An image at left labeled aluminum atom has a mix of red and blue balls in its center and 3 concentric black rings around the center. The inner ring has 2 small green balls on it. The middle ring has 6 small green balls on it. The outer ring has 3 small green balls on it. A blue arrow leads to an image at right labeled aluminum ion with a mix of red and blue balls in its center. 2 concentric black rings around the center. The inner ring has 2 small green balls on it. The middle ring has 6 small green balls on it."/>

An object weigh 40n in air ,weigh 20n when submerged in water,and 30n when submerged in a liquid of unknown liquid density.what is the density of unknown of liquid?

Boiling water is an example of physical change. true or false

69. air frictionthe velocity of the satellitea. decreases b. increases c. sometimes increases sometimedecreases d. no effect at all70. the unit of gravitational potential energy isa.jouté b.watt c. newtond.pascal71. which of the following is not influenced by a magneta. cobalt b.copper c.irond. nickel72. one joule of work done in one second by unit positive chargea.1 watt b.1 volt c.1 js d. none73. the most deviated colour of light after passing through a prisea. violet b.red c. green d.yellow4. a coin is placed below a beaker fill with water upto 12 cm isdisplaced by water isa. 9cm b.6cmс.3cmd.7cm