What is the total distance of a student who walks 5 blocks west, 5 blocks north, 6 blocks east, and then 5 blocks south?

Explanation:

The student walks;

       5 blocks west;

       5 blocks north

       6 blocks east

       5 blocks south

Now, distance is sum of all the length of the path covered.

 Distance  = 5 blocks + 5 blocks + 6 blocks + 5 blocks = 21 blocks

The total distance travel by the student is 21 blocks.

5 w for 1hr = 5x60x60 joules=300x60=3000x6=18,000j as total energy conversion. efficiency of bulb needed for radiant to thermal within 18000