Where must a pin be placed before a concave mirror of radius of curvature 300mm to form an image 400mm from the mirror which is: a. real b. virtual?

Aquantity of gas has a volume of 1.5 m3 and an absolute pressure of 95 kpa. when the gas is compressed to a volume of 0.5 m3, what is the new absolute pressure of the gas? (assume that there’s no change in temperature.)

Which compound is held together by the electrostatic force between two ions? a. co2 b. cci4 c. h2s d. mgf2

This chart shows characteristics of three different types of waves. which statement is best supported by the information in the chart? wave x and wave y are mechanical waves, and wave z is an electromagnetic wave. wave x and wave y are electromagnetic waves, and wave z is a mechanical wave. wave x and wave z are electromagnetic waves, and wave y is a mechanical wave. wave x and wave z are mechanical waves, and wave y is an electromagnetic wave.