Final answer:
For vertical shores in construction, a minimum of three is typically required in a group, but the specification may vary. Likewise, when calculating the fourth side of a land plot with three known sides, the fourth side will be equal to the opposite side if the plot is rectangular.
Step-by-step explanation:
In construction, the minimum number of vertical shores required, spaced equally, horizontally, in a group is three. However, it is important to note that the specific number may differ based on the structural requirements, local building codes, and the specific conditions of the construction site.
Similarly, when a farmer measures a four-sided plot of flat land and has the measurements for the first three sides, they can calculate the fourth side by using the principles of geometry. If the land plot is to be a rectangle, the lengths of opposite sides must be equal. Therefore, the length of the fourth side, D, would be equal to the length of side A if sides B and C are the lengths of the other two sides. The orientation would be parallel to side A.