Final answer:
To find out how many contour lines would be between sea level and an elevation of 175 feet with a contour interval of 50 feet, divide the elevation by the contour interval. This results in 3.5, meaning there will be three full contour lines, since a half contour line is not possible.
Step-by-step explanation:
The student has asked how many contour lines would be drawn between sea level and an elevation of 175 feet on a topographic map if the contour interval is 50 feet. To answer this, we would divide the total elevation by the contour interval. In this case, 175 feet divided by a 50 feet contour interval equals 3.5.
Since contour lines represent increments of the contour interval, and we cannot have half of a contour line, we would have three full contour lines representing 150 feet (3 x 50 feet) and some extra elevation that is not enough to require a fourth full contour line. Thus, the answer would be 3 contour lines (option b).
It's important to note that contour lines are drawn only for whole multiples of the contour interval. So, even though there is an elevation of 175 feet, it does not meet the 200 feet requirement for a fourth contour line, which would be represented by a fourth contour line.