The_base_diameter_of_a_conical_helix_is_100_mm_and_other_end_diameter_is_80_mm._The_height_of_helix_is_50_mm._What_is_the_angle_between_the_base_and_slanting_side_is?$

• A. 58 degrees
• B. 79 degrees
• C. 89 degrees
• D. 45 degrees