A4.0 w led bulb produces 240 lumens. what is the efficacy of the bulb? 1. 1.7 lm/w 2. 60 lm/w 3. 236 lm/w 4. 244 lm/w

Efficacy is the ratio of light output from a lamp or a bulb to the electric power it consumes and is measured in lumens per watt (LPW).
In this case; the power is 4 watt and the number of lumens is 240.
Efficacy = lumens/power
            = 240/4
            = 60 lm/W
Thus the efficacy of the bulb is 60 lm/W

its B) 60

Explanation:

Neptune is the eighth planet from the sun. it was the first planet to get its existence predicted by  mathematical calculations  before it was actually seen through a telescope on sept. 23, 1846. irregularities in the orbit of  uranus  led french astronomer alexis bouvard to suggest that the gravitational pull from another celestial body might be responsible. german astronomer johann galle then relied on subsequent calculations to   spot neptune via telescope. previously, astronomer galileo galilei sketched the planet, but he mistook it for a star due to its slow motion. in accordance with all the other planets seen in the sky, this new world was given a name from greek and roman mythology — neptune, the roman god of the sea.