Answer:
He has 30 penguins and 10 cats.
Step-by-step explanation:
Let's define the variables:
C = number of cats.
P = number of penguins.
We know that he has a total of 40 pets, then:
C + P = 40
We also know that the total heads (40 heads, each animal has one) plus the number of wings (P*2, each penguin has 2) is equal to the number of feet of his pets (4*C + 2*P, because each cat has 4 paws, and each penguin has 2)
Then we have the equation:
40 + 2*P = 4*C + 2*P
Notice that in the second equation we have the term 2*P in both sides of the equation, then we can just subtract 2*P in both sides to get:
(40 + 2*P) - 2*P = 4*C + 2*P - 2*P
40 = 4*C
Now with this, we can find the value of C.
40/4 = C = 10
Then he has 10 cats.
Now we can replace this in the equation:
P + C = 40
to find the value of P
P + 10 = 40
P = 40 - 10 = 30
P = 30
He has 30 penguins.
Radius = r = 1 foot
Angular velocity = w = 1 revolutions in 4 seconds
So,
w = 0.25 revolutions per second
Since,
1 revolution = 2π radians
We can write the above equation as:
w = 0.25 x 2π radians per second = 0.5π radians per second
Linear Velocity = v = r w
Using the values, we can write:
v = 1 x 0.5π
= 0.5 π
= π/2 feet per second
Therefore, the correct answer is option B
Its 20400
× 10
That equals 204,000. Hope I helped.
Answer is 2 (answer choice a)
