Answer:

Step-by-step explanation:
we know that
The equation of a exponential growth is equal to

where
a is the initial value
r is the rate of growth
x is the time in hours
y is the value of the quantity
we have

substitute


For x=22 hours
substitute

Answer:
Direction parabola opens upward.
Vertex of parabola is (27,-9).
Axis of symmetry is
.
Step-by-step explanation:
Note: Option sets are not correct.
The vertex form of a parabola is
...(1)
where, (h,k) is vertex and x=h is the axis of symmetry.
If a<0, then parabola opens downward and if a>0, then parabola opens upward.
The given function is
...(2)
On comparing (1) and (2), we get
, so direction parabola opens upward.
, so vertex of parabola is (27,-9).
So, axis of symmetry is
.
Answer:
3000
Step-by-step explanation:
The annual interest rate is 3.5%.
Solution:
Given Interest (I) = $26.25
Principal (P) = $500
Time (t) = 18 months
Rate of interest (r) = ?
Time must be in years to find the rate per annum.
1 year = 12 months
Divide the time by 12.
Time (t) =
years
Now, find the rate of interest using simple interest formula.
<u>Simple interest formula:</u>






⇒ r = 3.5%
Hence the annual interest rate is 3.5%.