Acrate is at rest on the ground. what force or forces are acting on the crate?
a.
there are no forces acting on the crate.
b.
the weight of the crate is acting downward on the crate.
c.
the ground is exerting a force equal to the weight of the crate upward on the crate.
d.
the weight of the crate is acting downward on the ground and the ground is exerting a force equal to the weight of the crate upward on the crate.

Asolution contains 180 g of glucose (c6h12o6) and 162 g of water. what is the mole fraction of glucose?

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

Calculate the percent composition by mass of each element in al(oh)3. use at least three significant figures.