Answer: 120 seconds
Step-by-step explanation: In order to find the maximum value of a function, you can take the derivative of the function and equalize the result to 0.
f'(x)=(-3x^2 + 12x)'=-6x+12=0
x=2
When x is 2, the function will reach its maximum value.
f(2)=-3(2)^2 + 12.2 = -12 + 24 = 12
The maximum value (f(x)) is equal to 12 and the time passed is 2 minutes which is equal to 120 seconds.
Answer:
331/150
Step-by-step explanation:
662/3% = (662/3)/100=662/300=331/150
The number of ways of choosing 4 digits from 10 digits without replacement ( order is important) is
. This is the number of all possible permutations of choosing 4 from 10. The first 4 numbers of your phone number is a unique 4 digit number(4 different digits). The required probability is

$5.25 divided by 25 = .21 cents each
The answer is A) the height of students