Q4: A prism in air with a 6-degree apical angle, and a refractive index of 1.50, held Base Down, has a power of .., and an object observed through this prism will appear to be displaced .. (Fill-in-the-blanks) Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a 4.00 PD; Up b 4.00 PD; Down C 5.25 PD; Up d 5.25 PD; Down