Answer:
3rd option
Step-by-step explanation:
A direct variation is expressed in this form:
y = kx
1. y - 4x = 8
y = 4x + 8 is not a direct variation
2. y + 2 = 7x
y = 7x - 2 is not a direct variation
3. y - 3x = 0
y = 3x is a direct variation
4. y = 5x - 2
y = 5x - 2 is not direct variation
Answer:
the maximum concentration of the antibiotic during the first 12 hours is 1.185
at t= 2 hours.
Step-by-step explanation:
We are given the following information:
After an antibiotic tablet is taken, the concentration of the antibiotic in the bloodstream is modeled by the function where the time t is measured in hours and C is measured in 

Thus, we are given the time interval [0,12] for t.
- We can apply the first derivative test, to know the absolute maximum value because we have a closed interval for t.
- The first derivative test focusing on a particular point. If the function switches or changes from increasing to decreasing at the point, then the function will achieve a highest value at that point.
First, we differentiate C(t) with respect to t, to get,

Equating the first derivative to zero, we get,

Solving, we get,

At t = 0

At t = 2

At t = 12

Thus, the maximum concentration of the antibiotic during the first 12 hours is 1.185
at t= 2 hours.
Answer:
<em>The number of </em><em>pine tree is 119</em><em> and the number of </em><em>elm tree is 187.</em>
Step-by-step explanation:
The ratio of pine trees to elm trees in a park is 7:11
Let us assume that the number of pine tree is 7x and the number of elm tree is 11x.
It is also given that, there are 68 more elm trees as compared to the pine trees.
i.e 



Hence, the number of pine tree =
and the number of elm tree = 