b$)$ Madam Anite intends to construct a $200$ mm thick perimeter wall of total length $120$ meters around her plot of land at Gayaza out of clay bricks or concrete blocks.

Cost of a $400200200$ concrete block delivered to site is Ugx. $5,800,$ Cost of a $200100100$ clay brick delivered to site is Ugx. $250,$ a $50$ kg bag of cement delivered to site costs Ugx. $34,500,$ a cubic metre of sand delivered to site costs Ugx. $101,500,$ labour constants for brickwork are $0\mathrm{.}9$ unskilled and $1\mathrm{.}8$ skilled hours; whereas labour constants for concrete blockwork are $0\mathrm{.}55$ unskilled and $1\mathrm{.}1$ skilled hours. Unskilled hours includes mixing of mortar and moving materials near to skilled labourers. Skilled hours is at a rate of Ugx$\mathrm{.}6,580$ and unskilled is at a rate of Ugx. $3,290.$ Use mortar mix of $1$:$5$; and joints of $25$ mm and $50$ mm for block and brick works respectively. Allow $25\%$ for profit and overheads, $25\%$ for voids when water is added to mortar, $1\mathrm{.}4$ ton $/m^3$for cement, $1\mathrm{.}3to\frac{n}{m^3}$ for moist sand, $1\mathrm{.}5to\frac{n}{m^3}$ for dry sand densities and $5\%$ waste for

cutting of bricks$/$blocks$.$

i$)$ Determine the cost of a cubic metre of mortar of the above mix arrangement. $[7$ marks$]$

ii$)$ Using the results in i$),$ explain to her in terms of construction costs what the differences would be; to erect the walls from dpc to a height of $2\mathrm{.}00$ metres ignoring finishes. $[25$ marks$]$