Indicate Whether the Function Is One-To-One $S ( r ) = 4 \pi r ^ { 2 }$

question 65

Multiple Choice

Indicate whether the function is one-to-one.
-The surface area of a balloon is given by $S ( r ) = 4 \pi r ^ { 2 }$ , where $r$ is the radius of the balloon. If the radius is increasing with time $t$ , as the balloon is being blown up, according to the formula $r ( t ) = \frac { 4 } { 5 } t ^ { 3 } , t \geq 0$ , find the surface area $S$ as a function of the time $t$ .

• A) \(S ( r ( t ) ) = \frac { 64 } { 25 } \pi t ^ { 9 }\)
• B) \(S ( r ( t ) ) = \frac { 16 } { 25 } \pi t ^ { 6 }\)
• C) \(\mathrm { S } ( \mathrm { r } ( \mathrm { t } ) ) = \frac { 64 } { 25 } \pi \mathrm { t } ^ { 6 }\)
• D) \(\mathrm { S } ( \mathrm { r } ( \mathrm { t } ) ) = \frac { 64 } { 25 } \pi \mathrm { t } ^ { 3 }\)

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