21.) is clue
I don't know the others I'm sorry...
The net amount they raise is the amount they receive minus what they pay in expenses.
They receive:
$10,000 fixed amount in donations
$55 per person
They pay:
$15 per person
If there are x number of entries, they receive 55x from the entries.
Also, they pay 15x for the entries.
The net amount they raise is amount they receive min us amount they pay:
55x + 10,000 - 15x
which simplifies to
40x + 10,0000
They want to raise at least $55,000.
At least $55,000 means $55,000 or more.
They want to raise an amount greater than or equal to $55,000.
Now we write the inequality:
40x + 10,000 >= 55,000
Now we solve the inequality for x, the number of entries.
40x >= 45,000
x >= 1125
They must have 1125 or more race entries to raise $55,000.
The formula of cone's capacity is V = (1 / 3) (pi x r x h)
we know that r = 3.5, we must find h, the slant height is H=6.5, applying pythagorean theorem h ^2 = H^2, so h= sqrt (H^2 - r^2)
h = sqrt (6.5^2 - 3.5^2) = 5.47
finally, V = (1 / 3) (3.14 x 3.5 x 5.47) = 20.03 cm^3
the surface are is A = pi x r x H = 71.43 cm^2
Consider a<span> right triangle with </span><span>hypotenuse of 1.
sin x means to divide the side in front of the angle by </span>hypotenuse<span>
cos x means to divide the side beside the angle by hypotenuse
we know that a^2+b^2=c^2 now divide two sides by c^2

c is 1 also a/c means sinx and b/c is cos x so
sin^2(x)+cos^2(x)=1
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