Solve the Problem $256 \mathrm { ft } / \mathrm { sec }$

question 218

Multiple Choice

Solve the problem.
-A professional fireworks team shoots an 8-in. mortar straight upwards from ground level with an initial speed of $256 \mathrm { ft } / \mathrm { sec }$ .
a. Write a function modeling the vertical position $s ( t )$ (in $\mathrm { ft }$ ) of the shell at a time $t$ seconds after launch.
b. The spectators can see the shell rising once it clears a 768-ft tree line. From what period of time after launch is the shell visible?

• A) a. \(s ( t ) = - 16 t ^ { 2 } + 256 t\)
• b. The spectators can see the shell between 4 and \(12 \mathrm { sec }\) after launch.
• B) a. \(s ( t ) = - 16 t ^ { 2 } + 256 t + 768\)
• b. The spectators can see the shell between 4 and \(24 \mathrm { sec }\) after launch.
• C) a. \(s ( t ) = - 32 t ^ { 2 } + 256 t\)
• b. The spectators can see the shell between 4 and \(12 \mathrm { sec }\) after launch.
• D) a. \(s ( t ) = - 32 t ^ { 2 } + 256 t\)
• b. The spectators can see the shell between 4 and 24 sec after launch.

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Definitions:

Afferent Arterioles

Small blood vessels that carry blood to the nephrons in the kidney, playing a key role in regulating blood pressure and filtration.

Papillary Ducts

Channels in the kidneys through which urine flows from the collecting ducts to the renal pelvis.

Renal Pelvis

The central part of the kidney where urine collects before moving into the ureter.

Minor Calyces

Small funnel-shaped structures in the kidney that collect urine from the nephrons and pass it to the major calyces.