Hurry !

the city is using sand trucks to place sand on the road during icy conditions. which best explains the use of sand?

a. the sand increases friction by increasing surface area.
b. the sand increases friction by increasing roughness.
c. the sand decreases friction by increasing surface area.
d. the sand decreases friction by increasing roughness.

Ahypothrticalax type of ceramic material is known to have a density of 2.10 g/cm3 and a unit cell of cubic symmetry with a cell edge length of 0.57 nm. the atomic weights of the a and x elements are 28.5and 30.0 g/mol, respectively. on the basis of this information, which of the following crystal structures is (are) possible for this material: sodium chloride, cesium chloride, or zinc blende

Which statement describes both homogeneous mixtures and heterogeneous mixtures?

No copying 15 pts how does a free-body diagram tell you about the net force on an object?