Answer:
Time t = 2 seconds
It will reach the maximum height after 2 seconds
Completed question;
Amir stands on a balcony and throws a ball to his dog who is at ground level. The ball's height, in meters above the ground, after t seconds that Amir has thrown the ball is given by:
H (t) = -(t-2)^2+9
many seconds after being thrown will the ball reach its maximum height?
Step-by-step explanation:
The equation of the height!
h(t) = -(t-2)^2 + 9 = -(t^2 -4t +4) + 9
h(t) = -t^2 +4t -4+9
h(t) = -t^2 + 4t +5
The maximum height is at dh/dt = 0
dh/dt = -2t +4 = 0
2t = 4
t = 4/2 = 2
Time t = 2 seconds
It will reach the maximum height after 2 seconds
Answer:
30units,2900
Step-by-step explanation:
Given that Country Motorbikes Incorporated finds that it costs $400 to produce each motorbike, and that fixed costs are $1600 per day.
The price function is p(x) = 700 − 5x, where p is the price (in dollars) at which exactly x motorbikes will be sold.
If x units are produced and sold we have
Costs for x units = variable costs *x +Fixed costs 
Sales revenue = no of units sold * price = 
Profit funciton = P(x) = Sales revenue - Total cost
= 
To get maximum profit we use derivative test I derivative =0 and II derivative =negative

Producing 30 units will maximize the profit.
Max profit
=P(30) = 2900
Up and down up and down up and down
There is a 1 in 15 chance it could occur. The more numbers you add, the rarer the chance. This does not guarantee that it will occur in 15 tests.
Answer:
2 books
Step-by-step explanation:
If 7 books= 1 box
Then 30 books= 30÷7= 4 boxes with a remainder of 2 books
Therefore books left over= 2 books