Which is a negative effect of these chemicals on society? a. polluting the water supply b. contributing to greenhouse gases c. feeding harmful bacteria in the soil d. making it difficult for crops to grow

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? a. the balloons both rise. the cold balloon is larger than the warm balloon. b. the balloons rise at the same rate. both balloons are the same size. c. the warm balloon expands and rises. the cold balloon shrinks and sinks. d. the cold balloon expands and rises. the warm balloon shrinks and sinks.

Describe the difference between a. a hypothesis and a theory and b. an observation and an experiment.

An object of mass 10.0 kg and volume 1000 ml and density 10 g/ml sinks in water who’s density is 1.0 g/ml. what is the mass of the water which has been displaced in kilograms