Answer:
385 cards
Step-by-step explanation:
First, find 40% and 25% of 1100.
2/5 * 1100
2200/5 = 440 cards dated before 1970
1/4 * 1100
1100/4 = 275 cards dated between 1970 and 2000
Then add the two amounts together.
440 + 275 = 715 cards between pre-1970 and 2000
After that, subtract your new sum from 1100.
1100 - 715 = 385 cards after 2000
(Or to make it easier, just find 35% of 1100.)
Here's our equation.

Let's reorder this so t² comes before t.

We want to find out when the ball hits the ground. Essentially, <em>what is t when h=0?</em>
Let's plug in 0 for h and solve.

From here we can use a number of methods to solve.
Methods such as splitting the middle, quadratic formula, etc. are not necessary for this equation, however. The best method here is just plain factoring.
-16t² and 176t are both divisible by 16t.

Now we want t to equal zero. If either of those factors were zero, then the whole thing would be zero when we multiply by it. The first option is obvious. If t were 0, 16t would be 0. That's when the ball is first kicked off the ground. The other, 11-t, works out to be
t = 11.
180 because it goes up by 6's every time so the answer is D.
Dx/dt = 6 sint cost
Open brackets first