$54.$ The application of potassium sulfate $($K$$SO$)$ is generally recommended over potassium chloride $($KCl$)$ in chloride$-$sensitive crops because:

$-$ A$)$ K$$SO$$ is less soluble in water, reducing leaching.

$-$ B$)$ K$$SO$$ provides sulfur, an essential macronutrient, in addition to potassium.

$-$ C$)$ KCl has been shown to be phytotoxic to most crop species.

$-$ D$)$ K$$SO$$ significantly enhances soil pH compared to KCl$.$

$55.$ If a fertilizer application results in a $20\%$ increase in crop yield from a baseline of $5$ tons per hectare, what is the new yield per hectare?

$-$ A$)5\mathrm{.}5$ tons

$-$ B$)6$ tons

$-$ C$)6\mathrm{.}5$ tons

$-$ D$)7$ tons

$56.$ The use of nitric acid in the agricultural industry is crucial for:

$-$ A$)$ Direct soil pH adjustment.

$-$ B$)$ Producing nitrogen$-$based fertilizers.

$-$ C$)$ Enhancing plant resistance to pests.

$-$ D$)$ Increasing water retention in sandy soils.

$57.$ An agronomist is comparing the cost$-$effectiveness of different nitrogen fertilizers. If the price per unit nitrogen is lower for urea compared to ammonium nitrate, but the volatilization loss for urea is higher, what factor should primarily influence the agronomist's recommendation?

$-$ A$)$ The crop type being grown

$-$ B$)$ The local climate and weather patterns

$-$ C$)$ The soil pH

$-$ D$)$ The method of fertilizer application