PLEASE HELP!! Ecosystem services are benefits that healthy, diverse ecosystems provide to humans. List some ecosystem services provided by a healthy biodiversity on Earth and describe how our lives would be changed without these.

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

How many moles of oxygen gas are produced from the decomposition of six moles of potassium

In one or two grammatically correct sentences, write a definition for the term molecule geometry