Question

The highest surface wind speeds at map time were along the region of the strongest horizontal pressure gradient across the upper Plains States. The wind speed at Fargo on the North Dakota-Minnesota border, and Des Moines in central Iowa, was about ________ knots.

a) 10
b) 20
c) 30
d) 40

Answer 1

Based on the provided wind velocity information, the wind speed values at Fargo and Des Moines closest to the given options would be approximately (b) 20 knots.

Step-by-step explanation:

The wind speeds in Fargo on the North Dakota-Minnesota border, and Des Moines in central Iowa, are being queried in relation to a horizontal pressure gradient. The question likely refers to wind velocity values annotated in specific regions on an educational wind map which delineates speed zones according to different colors corresponding to velocity ranges.

Given that nothing on the map exceeds 9 m/s, converting this to knots (where 1 m/s approximately equals 1.944 knots), the nearest highest range in knots does not exceed approximately 17.5 knots. The options provided in the question are 10, 20, 30, and 40 knots.

With the wind speeds from the map not exceeding 17.5 knots, the closest and most accurate answer from the provided options would be 20 knots, considering it as an upper approximation of the actual values.