The focal length of a bi-convex thin lens is 10 cm. The focal length of a convex-concave thin lens is -20 cm. If placing them in parallel and in close contact, the compound focal length in cm is

The image below shows numerous volcanic mountains in the pacific northwest. what is the most likely cause of the volcanic and earthquake activity in this region?

Determine the moment of the force f about an axis extending between a and c. express the result as a cartesian vector. a is at the origin, c is at (4,3,0) and f = (4i + 12j -3k) lb coming out of b (4,3,-2).

Drag the tiles to the correct boxes to complete the pairs. match the jobs with the education requirements. childcare director clinical psychologist concierge cosmetologist vocational school and state licensure arrowright on-the-job training arrowright a ph.d. with licensure or certification, depending on the state in which you live arrowright a bachelor’s degree in early childhood development arrowright