Step 1 of 3
Implicit costs are those cost which are indirect by nature and even though they have financial implications still they are not recorded in expenses.

Step 2 of 3
a.

The company was producing 62 million tons of greenhouse gases annually. Total emission reduction per year is:



So, to reduce 3.1 million tons of greenhouse gases, $1.2 billion or 1200 million was spent. So, the implicit cost of every ton of greenhouse gas is calculated as follows:



Thus, the implicit cost of every ton of greenhouse gas is.

Step 3 of 3
b.

Total emission reduction per year is:



So, to reduce 90 million tons of greenhouse gases, total capital required is :



Thus, the capital needed to reduce greenhouse gas by 3% is .