Question $3[22]$

$3\mathrm{.}1$ The South African Department of Agriculture is interested in analysing the domestic market for maize. The chief economist of the Department of Agriculture estimated the following equations for the demand and supply curves of maize:

The demand for maize: $Qd=300-2P+4.$

The supply of maize: $,Qs=3P-50$

where I is the average income measured in thousands of rands.

$3\mathrm{.}1\mathrm{.}1$ If I $=25,$ what is the market$-$clearing price and quantity for maize?

$(5)$

$3\mathrm{.}1\mathrm{.}2$ If I $=50,$ what is the market$-$clearing price and quantity for maize?

$(5)$

$3\mathrm{.}1\mathrm{.}3$ Draw a graph to illustrate your answers to questions $3\mathrm{.}1\mathrm{.}1$ and $3\mathrm{.}1\mathrm{.}2.$

$(5)$