Answer:
13 ft/s
Step-by-step explanation:
t seconds after the boy passes under the balloon the distance between them is ...
d = √((15t)² +(45+5t)²) = √(250t² +450t +2025)
The rate of change of d with respect to t is ...
dd/dt = (500t +450)/(2√(250t² +450t +2025)) = (50t +45)/√(10t² +18t +81)
At t=3, this derivative evaluates to ...
dd/dt = (50·3 +45)/√(90+54+81) = 195/15 = 13
The distance between the boy and the balloon is increasing at the rate of 13 ft per second.
_____
The boy is moving horizontally at 15 ft/s, so his position relative to the spot under the balloon is 15t feet after t seconds.
The balloon starts at 45 feet above the boy and is moving upward at 5 ft/s, so its vertical distance from the spot under the balloon is 45+5t feet after t seconds.
The straight-line distance between the boy and the balloon is found as the hypotenuse of a right triangle with legs 15t and (45+5t). Using the Pythagorean theorem, that distance is ...
d = √((15t)² + (45+5t)²)
Answer:
D
Step-by-step explanation:
2000=1 ton so 4000=2tons
Answer:

Step-by-step explanation:
The experimental probability can be defined as the ratio of the number of times any particular event has occurred to the total number of times that event has taken place.
Experimental probability = P = No. of event occurrences / total number of occurrences.
In our question statement,
No of naturally occurring triplets are = 3375
Total number of births = 5 million = 5,000,000
Putting values in equation.


Step-by-step explanation:
The area that cow can graze is in the form of semicircle.
Radius of semicircle
Length of rope =14 m
Required area = 1/2 ×πr
=1/2×22/7×r^2
=1/2×22/7×14×14
=308m2