List of top Zoology Questions on Basic principles of cellular microscopy

What will be the value of the Numerical Aperture (NA), if the half aperture angle is 58° and oil-immersed objective is used for the process of light microscopy? (Answer up to 1 decimal place)
Which of the immune cells listed below are agranular?
P. Eosinophils
Q. Mast cells
R. Monocytes
S. T-cells