import math


def solar_zenith_angle(lat, solar_decline, hour_angle):
    """Returns Solar Zenith Angle in Degrees, with Latitude, lat, Solar Decline (Degrees), 
    solar_decline, Hour Angle (Degrees), hour_angle."""
    solar_zenith_angle = math.degrees(
        math.acos(
            math.sin(math.radians(lat)) * math.sin(math.radians(solar_decline))
            + math.cos(math.radians(lat))
            * math.cos(math.radians(solar_decline))
            * math.cos(math.radians(hour_angle))
        )
    )
    return solar_zenith_angle