the focal length of a concave mirror is 15cm. Calculate the image distance if an object is placed at the center of curvature​

A250-n box is at rest on a frictionless horizotal floor. then a person shoves the box with a non-zero force of magnitude p. which statement best describes the relationship betweeen p and the motion of the box after it was shoved? -the box will not move when p< 250n but otherwise will accelerate at a constant rate that is directly proportional to p - the box will begin moving at a speed that is directly proportional to p, then will gradually slow to a halt -the box will move with constant velocity at a speed that is directly proportional to p -box will accelerate across the floor at a constant rate that is directly proportional to p

1. when conducting a test on what kind of music increases the growth of plants, all of the following would fail to meet to fair test standard except (1 point) using different kinds of plants. giving some plants more water than others. exposing the plants to different types of music. using nutrient-rich soil for one and lesser soil for others. 2. engineering uses scientific thinking to solve real-world problems. (1 point) true false 3. what does it mean to test a hypothesis? (1 point) pass a quiz on other scientists’ results analyze only the results from scientific sources not make assumptions about how an experiment will turn out see if the results of an experiment are what the scientist predicted

Can anyone plz answer any of these. even if its one it will