Carbon dating of small bits of charcoal used in cave paintings has determined that some of the paintings are from 10000 to 30000 y old. Carbon-14 has a half-life of 5730 y. In a 1μg-sample of carbon from a live tree, the activity of carbon-14 is 6.4μCi. If researchers determine that 1μg of charcoal from a prehistoric cave painting in France has an activity of 1.6 μCi, what is the age of the painting? Express your answer using two significant figures.

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.

particle   p is an electron and particle q is a neutron