Mississippi Superlatives

For the river, name the longest river that flows through or along the border of Mississippi by total length of the river, not just its length in Mississippi.

For the lake, name the largest lake that touches Mississippi by total surface area, not just its area in Mississippi.

For the island, name the largest island with territory in Misssissippi by the total area of the island, not just its area in Mississippi.

For temperature records, name either the temperature in degrees Fahrenheit or the location where that temperature was recorded.