Given mapping is a function.
Domain: 
Range: 
Step-by-step explanation:
By observing Marco's mapping diagram we can see that every value in time is mapped to only one value in the cost. This means that there will be no repetition or same output to two different outputs so given mapping is a function.
<u>Domain:</u>
Domain is the set of all inputs of a function. Here time is input so domain of function is:

<u>Range:</u>
Range is the set of all outputs of the function on domain so the range of the given function is:

Hence,
Given mapping is a function.
Domain: 
Range: 
Keywords: Domain, range, function
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Step-by-step explanation:
29+1/5r=
29+(1/5×-1/2)
29+1/10
291/10
=29.1
Answer:
$4
Step-by-step explanation:
Trey sold his $80 hockey stick for 25% less. This means that he received 75% of the $80. Convert the percentage to a decimal, so it will be .75. Multiple .75 by $80 and you will get the final answer which is $60.
Brandon sold his $80 hockey stick for 30% less. This means that he received 70% of the $80. Convert the percentage to a decimal, so it will be .70. Multiple .70 by $80 and you will get the final answer which is $56.
Trey received $4 more for his hockey stick.