Question

You are a scientist working on increasing the efficiency of appliances to waste less

Answer 1

Answer: lightbulb 1: 200 joules in, 50 joules wasted, 150 joules out

Explanation:

Answer 2

Lightbulb 1 has the lowest  percentage of energy lost as waste : 25%

Further explanation

Given

The input, output, and waste energy of Lightbulb

Required

The lowest  percentage of energy lost as waste.

Solution

Lightbulb 1 :

$\tt \%energy~lost=\dfrac{50}{200}\times 100\%=25\%$

Lightbulb 2 :

$\tt \%energy~lost=\dfrac{30}{100}\times 100\%=30\%$

Lightbulb 3:

$\tt \%energy~lost=\dfrac{100}{150}\times 100\%=66.7\%$