Answer:
a.73.3%
b.26.6%
Step-by-step explanation:
a. The efficiency is the energy output, divided by the energy input, and expressed as a percentage.
#Given the energy input as 1500J and the subsequent output as 1100J, the TV's efficiency is calculated as:

Hence, the TV has an efficiency of 33.3%
b. From a above, we know that the TV has an output of 1100J and input of 1500J.
-We therefore calculate it's wastage as the difference between output and input:
Wastage=Energy Input-Energy Output=1500J-1400J=400J

Hence, the TV has wasted of 26.6%