CAPE Environmental Science Unit 1 · 2013 · Paper 2 · Question 5(a)(ii)

A government introduced a 100% tax refund on purchasing and installing solar water heaters in 1978. Figure 5 tracks sales from 1974 to 1990.

Calculate the average annual increase in solar water heaters sold during the first five years following the introduction of the tax incentive policy.

This question uses a figure or table from the paper — you'll see it when you practise.