Please, help me!! A block of wood weighing 18 pounds rests on an inclined plane that makes an angle of 60 with the horizontal. How much of the friction force is needed to prevent the block from sliding on the plane?

___lb.

Aportion of a line bounded by two points is defined as

Two streets intersect at a 30- degree angle. at the intersection, the are four crosswalks formed that are the same length. what type of quadrilateral is formed by the crosswalks?

He mass of a single atom of carbon can be found by dividing the atomic mass (12.01 g) by 6.022 x 10^23. which is the mass of a single carbon atom, correctly written in scientific notation with the correct number of significant figures?