California is a floatplane pilot’s paradise, with lakes rang…

California is a floatplane pilot’s paradise, with lakes ranging from the scorching Salton Sea at 236 feet below sea level to high Sierra lakes above 10,000 feet. But elevation creates a challenge: as altitude increases, the air becomes less dense, and a floatplane needs a longer takeoff run to become airborne. Pilots account for this using density altitude, a measure that combines elevation with air temperature to capture the effective performance environment of the aircraft. The file ca_lakes.csv contains a list of California lakes along with basic data about each one, including the lake’s elevation and average summer air temperature. The density altitude at each lake can be estimated using two formulas. First, the International Standard Atmosphere (ISA) temperature at a given elevation is:

A pasture has experienced woody encroachment and most vegeta…

A pasture has experienced woody encroachment and most vegetation patches are dominated by unconsumable woody plants. Cattle are unable to access what little forage remains due to dense woody vegetation.  The manager intends to implement brush management (with follow up treatments to deplete seedlings and resprouts) to restore desirable forage species and increase cattle utilization and occupancy. Which arrow depicts the desired change in this patch?  Screenshot 2026-03-31 220330.jpg