The invention of agriculture
a. led to an increased birth rate and death rate.
b. provided a more dependable food supply.
c. allowed people to settle down in villages.
d. all of the above

Nerve cells are specialized to respond to stimulitrue or false?

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? question 8 options: the cold balloon expands and rises. the warm balloon shrinks and sinks. the balloons rise at the same rate. both balloons are the same size. the ballons both rise. the cold ballon is larger than the warm balloon. the warm balloon expands and rises. the cold balloon shrinks and sinks.

Paint and solvents pose no potential hazard to human health. select the best answer from the choices provided t f