What is the name of the process that describes the decrease in frequency

How does the image distance (di) of a convex lens compare with the image distance of a concave lens? a. the image distance of the convex lens is positive, and that of the concave lens is negative. b. both are negative for a virtual image. c. both are positive for a virtual image d. the image distance of the convex lens is negative, and that of the concave lens is positive.

True or false: the revolution of the earth creates day and night as it rotates around the sun

Lymphocytes known as blastocysts make antibodies that fight infection. select the best answer from the choices provided t f