The quadratic model is f(x) = -5x^2 + 200.
f(x) = 50 meters
x = time in seconds
50 = -5x^2 + 200
5x^2 = 150 // Here, divide both side by 5
x^2 = 30
x =

seconds
Or approximately 5.48 seconds
y=4x+40
x represents the number of minutes
y is the total
40 because he already graded 40 papers, and 4x because that's how many phred grades times the number of minutes
Answer:
Step-by-step explanation:
A coin has two faces, a head (H) or tail (T). Tossing a coin twice in succession would give the following sample size;
{HH, HT, TH, TT}
Given that: A = first toss is heads, B = second toss is heads, then:
i. P(A) = {HH, HT} = 2
ii. P(B) = {TH} = 1
iii. P(A∩B) = {HH} = 1
iv. P(B /A) = 