Which of these elements is least likely to react with other elements< br /> < br />
a. calcium< br /> < br />
b. argon< br /> < br />
c. sodium < br /> < br />
d. nitrogen< br /> < br />
e. oxygen< br /> < br />
f. chlorine

The free body diagram shows a box being pulled to the left up a 25-degree incline. the magnitude of the normal force is

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 2 options: 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 cold balloon expands and rises. the warm balloon shrinks and sinks. the warm balloon expands and rises. the cold balloon shrinks and sinks.

Astudent pushes a 60-n block across the floor for a distance of 10 m. how much work was done to move the block